Huawei Ascend G700-U10 Stock Firmware ROM (Flash File) download for your Huawei Android Smartphone. Included contains Flash Tool, USB Driver, and how-to Flash manual instructions. Huawei G700-U10 running on Android v4.2.1 Jelly Bean version which is manufactured by MediaTek MT6589 CPU. Use SP Flash Tool for flash Firmware on this device.
Step 1: Download and extract Huawei G700-U10 flash file on your Computer. After that, you will find Scatter Firmware images inside the folder. Now open SP Flash Tool and click on Scatter-loading button in Flash Tool and select the MT6589 Scatter file from Firmware.


SYRACUSE, New York — On October 29 and 30, the Near East Foundation co-presented a session on livelihoods development for returns and reintegration at a meeting convened in Geneva by the U.S. Department of State's Bureau for Population, Refugees and Migration (PRM).
The two-day stakeholder's meeting was organized to contribute to PRM's strategy for humanitarian assistance in Iraq and for Iraqis in Jordan, Syria, Lebanon, and Turkey.
Jina Krause-Vilmar, NEF Director of Program Development, presented the livelihoods session along with Michael Pillinger, International Organization for Migration's Iraq Country Director.
The NEF and IOM session discussed models for livelihoods support and advocacy needs in the region. The co-presenters facilitated a conversation with participants to brainstorm on needs, strategies, and desired results of possible interventions.
The invitation-only meeting was spearheaded by Deputy Assistant Secretary Kelly Clements, and attended by senior UNHCR and UNDP staff, as well as representatives from U.S. government agencies, multilateral organizations, and international development agencies.
With funding from PRM, NEF is leading a one-year initiative to enhance the economic resilience of impoverished Iraqi and Jordanian women and youth in Zarqa, Jordan.


I watched a lot of movies in college and a lot of those movies weren't exactly Oscar-worthy, so I decided to put together a list of the worst movies I've ever watched from beginning to end.
I started by writing down every movie I wish I had never started to begin with, let alone sit through til the closing credits. Then I narrowed it down to the ten I absolutely refuse to ever watch again.
At one time my roommate was dating a guy who worked at Hollywood Video, so we would ask his advice on new releases. Usually he was spot-on with his recommendations, but then he told us we should watch 'Hard Candy'.
In short, it was like watching a train wreck. So horrible but we were unable to look away. The trailer even warns against it.
The worst part? You watch a castration. It doesn't matter that Hayley isn't really performing a castration on Jeff, you see it anyway.
There are so many unanswered questions with this movie. While there is a resolution to the conflict at hand, you're left wondering who the characters are and what motives drive them to do what they did.
This movie had so much potential, but it never delivered on any of it. Liam Neeson played an amazing role, as usual, but his performance just couldn't save it. There are too many questions left unanswered. Is Christina Ricci's character truly dead, or is Neeson's character some psychopath who just takes joy in burying people alive? Ricci's character is also very unlikable for a heroine. I found myself annoyed with her for the majority of the movie, partially because of her ineffectiveness.
This movie could have been great, but it was missing… something. The plot line was flat, no twists or turns to keep you interested and nothing climactic to make it worth it.
The creepiest part of the entire movie was the little boy, and I'm still not sure what his purpose in the movie was.
What can I say about this movie other than remark on the stupidity of it? Yes, there were parts I laughed at (for the sheer stupidity of the situation) but they were few and far between. Mostly I was shaking my head and wondering why on earth we rented this movie.
I do have a bit of trivia for you concerning this movie though that may have contributed to the badness - six pro wrestlers made appearances in it, including The Great Khali, Kane, The Big Show and Chris Jericho.
I've previously reviewed this movie on my blog, so I won't repeat myself. Instead, I'll provide you the link to that review.
I watched this movie with a friend of mine after a really rough weekend. By the time we finished it, we both looked like Rodin's 'The Thinker'. We had no idea what had actually happened. There was one point in the movie where we thought we had found a plot line only to discover a few scenes later that things were just as jumbled as ever.
I should have known better than to watch this movie when I saw who directed it. I've never been a fan of M. Night Shyamalan, The 6th Sense notwithstanding. If I hadn't looked up the summary of this movie, I never would have figured it out. The plot wasn't helpful, the suspense was never seen through to a conclusion, and the viewer is left with nothing more than theories as to what actually happened.
I watched this movie with an ex-boyfriend. We both mistakenly thought it was about biological warfare. Instead it's about nature going on the attack. Now I'm not talking about animals going crazy. I'm talking about the wind. The wind blows and if you're out in it, you go crazy and kill yourself. It isn't explained, only theorized that it has something to do with the disappearance of bees … and that theory is only postulated in the first few minutes of the movie.
In order for a horror movie to be good, it has to make sense. That's where this movie fails.
My friends and I watched this movie our freshman year of college. We turned off the lights, closed the shades and all got our protective shields to hide behind (pillows/blankets) and prepared ourselves for the scariness we were sure was about to ensue. But that adrenaline rush we had prepared for never came. I didn't hide behind my shield once, and I'm the type of person who spends the majority of a scary movie watching with just one eye.
This is quite possibly the best viewer review I have ever read about a movie, so I thought I would share:"Allow me to save you $8 by offering something you can do at home that is just as entertaining as watching this movie. Go get a load of whites and throw it in your dryer. Now, add in one red sock. (Make sure everything's dry so you don't end up with a bunch of pink laundry.) Now, hopefully you have the kind of dryer that has the clear window in front. If you do, start the load and watch the laundry spin around. Every time you see the red sock pretend to be scared.
Halle Berry even earned a Razzie award for her performance in this movie, which she personally accepted. At least she was a good sport about it though.
This movie failed to bridge a connection with its audience. My roommate and I rented it because of what it was supposed to be about – a journalist going undercover to investigate her friend's murder. Sounds promising right? It was a major disappointment.
The acting was subpar, as is characteristic with many Halle Berry films I've seen (excluding XMen). Her character wasn't convincing at all. In fact, the movie wasn't convincing either. It had the sufficient amount of twists, but that's all it had. There was no substance to the movie, no depth to the characters, and when it was finally over there was a sense of relief despite the sense of incompleteness.
This movie is a bit of a blur to me. A lot of that is due to the fact that the movie was hard for me to follow. I typically like Mark Wahlberg, but in this film his character didn't invoke any response from me whatsoever. I never really understood who he was outside of a detective intent on bringing his family's killer to justice. Then there are the parts of the movie related to an addictive hallucinogen. They're just crazy, plain and simple.
These movies that I picked didn't make it onto IMDB's Bottom 100 list. The majority of those movies are ones I'd never heard of until doing my research for this post. However, most of the titles I did recognize were spoofs or parodies, so not exactly Oscar-worthy productions there.
And if you're looking for something slightly entertaining to do, head over to Rotten Tomatoes and check out their list of 25 movies so bad they're unmissable.
When I saw the title of this blog I was hoping you would have The Happening on here.
I couldn't not include that movie. It was awful, pure and simple. A total waste of time.
I heard a lot of negative stuff about The Green Hornet so I didn't watch it. Actually, I don't watch a lot of movies. Hehe.
Well, my friend, these are movies you should strive to avoid! They're definite wastes of time.
My dashboard half the time tells me I'm not following anyone.
I know, right! We thought it would be amusing, but even my boyfriend didn't like it.
I agree with your list! I'd like to add Liam Neeson's latest movie..Unknown! I just felt as if I should care more...shouldn't you be making me care more...then the end I was left thinking...WHO CARES!!!
I just recently watched that movie and have to confess that I had a hard time staying awake during the beginning. My boyfriend liked it though.


text:
R Madhavan makes sure not hurt feelings of his Tamil fans
By IANS-CT / June 11, 2010
Mumbai, June 11 (Calcutta Tube) Multilingual Indian actor R. Madhavan, who was conspicuous by his absence at the 11th International Indian Film Academy (IIFA) awards, says he makes sure that he doesn't do anything that hurts the sentiments of his Tamil fans.
'I wouldn't like to get into the politics of it because I'm an apolitical person. Even when I did 'Kannathil Muthamital', which had a bearing on LTTE activities, I did it for the love of Mani Ratnam, not politics. But yes I'd do nothing to hurt the sentiments of my Tamil fans. There were hundreds of messages on Twitter and the SMS imploring me to stay away from IIFA this year,' said Madhavan.
In fact, to show his solidarity with the Tamil community, Madhavan along with Kamal Haasan held the 'mahurat' of their new Tamil film 'Manmadanambu' in Chennai June 3 when all of the Indian film industry headed for Colombo for IIFA.
When Madhavan had done Ratnam's 'Kannathil Muthamital' on the workings and emotional pressures caused by the LTTE activities, his Tamil fans, whose network spreads from Tamil Nadu to Singapore to the US, were pleased by their hero's participation in a film that seemed to be a rare cinematic voice trying to understand their cause.
Many Bollywood stars skipped IIFA this year including its brand ambassador Amitabh Bachchan as well as superstar Shah Rukh Khan and according to reports, they gave it a miss following a boycott call from the south Indian film industry.
A statement issued by the South Indian Film Chamber of Commerce had said that southern stars and filmmakers would boycott all Bollywood stars who attend the IIFA in Colombo from June 3-5.
They have been campaigning against the island government and the alleged killing of civilian Tamils during the conflict between Sri Lankan army and the rebel Liberation Tigers of Tamil Eelam (LTTE).
Significantly, after hits like '3 Idiots' in Hindi Maddy has gone back to Tamil cinema on his Tamil fans' say-so.
'I kept getting hate messages about why I wasn't doing Tamil films. I hadn't done a Tamil film for a while. As for Hindi cinema, I've just completed 'Tanu Weds Manu', which is turned out really well,' says the actor who turned 40 June 1.
'On my birthday my wife and I headed for Pune to play golf with all my old friends. My wife is a really good golfer. She can beat me at the game any time. After playing the whole day, we headed back to Mumbai to our favourite restaurant. Satiated with Japanese wine we headed home…'
Tags: Indian actor, R. Madhavan
Driver-Bollywood film by Sudhir Mishra not based on Aditya Kripalini's script
Petition against Amitabh Bachchan dismissed

redpajama_set_name: RedPajamaCommonCrawl


What is a White Card in Australia?
A White Card in Australia is proof that you have completed a General Construction Induction Course enabling you to work within the construction industry in Australia. A construction White Card in Australia is a legal OH & S requirement for any person working on a construction site no matter how large or small the job.
Everyone from unskilled labourers through to skilled tradesmen must have a White Card certificate before stepping foot on site, and those caught without a White Card are subject to fines and may also find themselves uninsured in the event of an on-site accident. It is highly recommended that anyone looking for work within construction undergo their construction White Card training in Australia prior to seeking this type of employment.
The White Card training course is the entry level safety course for the construction industry and covers a range of OH & S topics. These topics cover an explanation of OH & S legal requirements, the identification of hazards within construction and ways to manage them, OH & S reporting processes and communication, and OH & S accident response procedures.
White cards can be obtained in a number of ways, but by far the most convenient is completing an online course. The online Narbil White Card training course can be done on any computer with internet, anywhere and anytime. The course takes an average of 2 to 4 hours to complete and can be taken over a single day or as many days as required. Narbil Online Training courses do not require payment until the applicant has completed the course and passed.
Although it is often recommended that you obtain your White Card in the state that you intend on working in, Narbil is issuing a National White Card (Australia) that should be recognised in all states and territories. New South Wales, Queensland, Western Australia and Victoria have all adopted the National Standard White Card Induction CPCCOHS1001A, issuing recipients with a potentially nationally recognised construction White Card.
Learn more about the Narbil White Card.


Proud of its LEED Gold certified status as one of the first green residential high-rise buildings in the nation, Tribeca Green offers residents the opportunity to lead a healthier, more eco-friendly lifestyle.
Designed for a new era of cleaner, energy-efficient luxury living by renowned architect Robert A. M. Stern, the property features spacious studios to three and four bedroom apartments with up to 1,800 square feet of extraordinarily flexible space. Gourmet kitchens feature Energy-Star rated Kitchen Aide stainless steel appliances, Euro-style cabinetry and marble counters. And in concert with Related's commitment to sustainability, and out of concern for the health and wellness of our residents, at Tribeca Green new residents and their guests have chosen a non-smoking environment. We are pleased to offer this indoor air quality enhancement at Tribeca Green.
Unique apartments with flexible spaces, including larger-format three- and four-bedroom options.
Direct access to green spaces, including Tear Drop Park and Rockefeller Park.
Wellness-oriented living, including triple-filtered fresh air vent for clean breathing, and LEED Gold certification.
A doorman attends the building.
The lobby includes comfortable gathering spaces.
Spacious layouts include room for families.
Gourmet kitchens include high-end finishes and stainless steel appliances.
Open floorplans offer residents a feeling of extra space.
Large windows let in natural light.
Residences range from studios to four-bedroom floorplans.
Apartment layouts are designed to provide flexible space.
On-site fitness center features state-of-the-art equipment.
The children's playroom features low-VOC paint and natural flooring.
Nature is incoporated in many of the amenity spaces at Tribeca Green.
Our Related Technology Concierge can help with digital problems.
The party room offers gracious space for entertaining.
Tribeca has downtown cool perfected, with its array of hip restaurants, fashionable nightclubs, upscale boutiques, and stylish cafes. Just a skip away is leafy Battery Park City, with a more casual vibe, leafy parks, and three of the city's best schools. The adjoining areas offer easy commutes to the financial center of Manhattan or up to Midtown, and quick access to the West Side Highway makes getting around the city — or out of the city for a weekend away — that much easier.


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text:
Oxford Audio Post Production Blog
Jacob on Mastering Audio Techniques!
Mastering is the final process in post production before the audio is sent off for duplication. It is considered by many to be the most important step. Mastering engineer Howie Weinberg describes it as "Photoshop for audio." This is an accurate statement as the process uses a variety of tools to enhance the recording to be as good as it can be. It needs patience and a meticulous ear for audio as the tiniest of adjustments can impact greatly on the final sound of the master. Moderation is key! Each engineer will have their own way of going about mastering however, they will all use the same kind of dynamic processing tools; EQ, compression, limiting, noise reduction and dithering to name a few. Unlike mixing which involves processing each individual track or instrument so that they fit together neatly in the stereo field, processing in the mastering stage is applied to everything.
The first step involves transferring the final mix into the preferred DAW (Digital Audio Workstation). The industry standard as always is Pro Tools, however there is a handful of software such as SADiE, Pyramix, Sequoia that have been written with mastering in mind. There aren't great differences between the DAWs, it is mostly dependant on the engineer's preferences. After that the "silence" between each track is edited. As CD players take a small amount of time to unmute after skipping a track, it is vital that there is a gap (around 300ms) of silence at the beginning so that the first transient of the song is not cut out.
The next stage is the most important and time consuming. It is the dynamic processing or "sweetening" of the audio to maximise the sound quality. This is done using the processing tools mentioned earlier. Equalization is applied in small amounts to balance the track. It is important that each frequency band is balanced with the rest so that they are complimenting each other rather than fighting for space. Compression is used to add punch and warmth to the mix as well as loudness. In mastering, a Multiband Compressor will be used. It does the same job as an ordinary compressor however it allows the engineer to compress sections of the frequency spectrum which makes it all the more accurate and efficient. Limiting will allow the loudness to be pushed further without peaking or clipping. Compression and limiting must be used in moderation, an overly compressed track that has been pushed too far will be left with a small dynamic range, making it sound flat and dull. The final stage in the "sweetening" chain is Dithering which is simply the application of a low level random noise if the audio is truncated. Truncation describes the reduction in resolution of audio i.e. from 24-bit to 16-bit. When this happens, the sound quality is diminished as the extra 8 bits are lost. By adding random noise, it helps in masking the distortion produced by truncation, making the many short-term errors much less noticeable to the listener. This is a very powerful tool should always be applied before truncation!
Once all of these steps are complete and both parties are happy, the final master can then be transferred to the final format (CD-ROM, half-inch reel tape, PCM 1630 U-matic tape, etc.) From this the song or songs can then be duplicated.
The success of mastering relies heavily on the monitoring and listening environment in which it was mastered. The better the speakers, the more detail is heard therefore the greater the accuracy. This goes for the processing tools used as well, professional standard EQ, compression and limiting help greatly in achieving a finer sound. This is why a professional recording studio set up is desirable. Mastering can be thought as the final push in highlighting what's great about a track or album. By carrying out each step correctly, it can make a good piece of audio into something well polished, professional sounding and marketable!
Click here for more details about how our music studio can help you with your audio mastering!
Audio Restoration and Enhancement
Audio restoration is a process used to reduce noise such as hiss, crackle, hum, etc. from audio recordings. Most modern techniques of audio restoration are performed in the digital realm on audio from an analogue source. The removal of unwanted sounds is usually performed in DAWs (Digital Audio Workstations) however there are also digital standalone de-clicker's, de-noiser's and dialogue noise suppressors. Although there are automated solutions, audio restoration is still a time consuming and complex process that often requires experienced audio engineers with a background in audio post production.
Record Restoration is a particular kind of audio restoration where the audio is converted from the analogue signal on a gramophone record (either 78, 45 or 33⅓ rpm). First the record is cleaned to remove surface noise that can be caused by dirt, then it is transcribed into the digital realm, where software is used to adjust equalization and volume. This from of audio restoration is however rarely used and gets harder the older the record is, due to the nature of the medium (playback causes gradual degradation of the recordings).
Above is a before and after shot of an audio recording that has been processed with the popular de-noising/de-hissing tool izotope RX. As you can see, the waveform has changed fairly drastically which would be represented in the improvement of the audio quality. Izotope RX is an extremely effective tool for removing a static noise or hum. It works by analysing a sample of the noise selected by the user. It then 'learns' the noise and subtracts it from the entire clip, often to inaudible or negligible levels.
Audio restoration is more than just adjusting volumes and de-noising files, it can have a huge impact, depending on what the audio is used for. We have worked on a number of projects where clients had potentially incriminating audio recordings but the audio quality was so poor that nothing could be understood. Audio restoration brings out the voices in spoken word recordings so that they can be transcribed and used as evidence in court. Clean audio can make a real difference and can very well be used as damning evidence or proving your innocence.
Click here for more details about how our music studio can help you with your audio recordings!
Audio Dialogue Replacement
Automated dialogue replacement is a technique employed to enhance or alter an actor's dialogue after a scene has been shot. It involves an actor watching the original video and re-performing each line in time with their lip movements. This could be needed because of a lacklustre vocal performance or to bring about a subtle change in the actor's lines, such as a slight change in inflection, or simply that some dialogue is needed for an animation or video game. One of the most common uses for ADR is unwanted background noise, such as police sirens in the background of a medieval set. This can be negated by shotgun microphones – a highly directional microphone that rejects sound off-axis – but even some background noise can bleed through. "Apocalypse Now" supposedly had 90% of the audio as ADR, due to very noisy sets.
Whilst some smaller, independent movies avoid ADR due to budgetary constraints, it can be indispensable since they may not be able to lock down and control the sound in certain sets in the same manner that a big budget blockbuster can. The origin's of ADR can be seen in the black-and-white days, where the pretty faces would perform in front of the camera and their less attractive counterparts would be hidden behind a microphone.
Considered by many as a necessary evil of the movie industry, it is a widely held view that the dialogue produced in ADR will rarely come close to the performance in the original shot. The actor's voice is often lower pitched and quieter (since they tend not to be as hyped up as they are on set). This can be countered by digitally shifting the pitch of the voice, recording in a more authentic environment or bringing the director into the studio to encourage the actor. There is also the challenge for the actor to get his lines perfectly in sync with his lips. The typical method involved a line running across the screen, with three beeps (followed by a fourth silent beep) counting down to the cue point.
Click here for an example.
The whole ADR process is nowhere near as mind-numbing as it was in the pre-digital era, where each individual segment of film (which required ADR) was put on a projector and cycled again and again until the dialogue was suitable. Thanks to digital editing, the recorded dialogue can be manipulated to better synchronise with the video, and some software is able to match the peaks of the newly recorded dialogue with the original, messy dialogue, such that it perfectly fits in with the video.
Since a large proportion of many films soundscape is built in post-production, is it even worth recording sound on set anymore? Absolutely, much of the original audio can easily be salvaged and spliced into the final mix, especially the background noise and general ambience to help everything sound more natural. It will also save a huge amount of time and money; most actors would rather keep their original performance than go into an ADR studio and re-record dialogue. All things considered, it is an invaluable tool that allows film makers to help mitigate several audio issues which can ruin a movie.
For more about our ADR facilities as well as other voice recording services at OAPP click here.
Oxford Audio post Production
Unit 36 Curtis Industrial Estate, North Hinksey Lane, Oxford OX2 0LX
Click here for Company Website
CLICK HERE TO ORDER CD FOR MASTERING ONLINE
We offer audio recording through Pro Tools HD10, GSSL mix bus compression and Neve summing. We have three acoustic spaces for recording audio including Oxford's largest drum room.
Recorded audio is mixed and mastered through pro-analogue gear and dedicated plugins from Waves, UAD, fabfilter as well as many other companies. Music recordings as well as spoken voice recordings can be edited and the audio enhanced professionally using this equipment.
We offer Source Connect to link studios around in different cities (or even around the world!) to the Oxford studio.
Our studio offers professional digital restoration to restore any audio in any format to its highest fidelity. Our clients are UK wide and our restoration has been used by the judiciary.
We can replicate your master CD DVD or USB. We design the packaging for you or work with your brief for a bespoke design.
Film, Video and Audio Tape conversion specialists. Our clients include Oxford City Council, The NHS and University of Oxford


text:
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@Component({
	selector:'feature-block'
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	templateUrl:'client/featured/feature-block.html'
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redpajama_set_name: RedPajamaGithub


text:
Location! Location! Location! The Albert Solheim Library is Forefront at PNCA's New Campus
Written by Kate Rubick, Lewis & Clark College
Photos by Dan Kelley, Lewis & Clark College
Approaching the Pacific Northwest College of Art, a renovated 1909 building in the North Park Blocks of Portland, I was impressed by its beauty — the ground floor is wrapped in high windows with curved tops, that were painstakingly recovered and restored. And through the windows, passersby can see bookshelves and lamps, people engaged in reading and study; the view inside is unmistakably the library.
(Click each thumbnail in the gallery below for the full photo and caption information.)
Entrance to the Albert Solheim Library at PNCA. Photo by Dan Kelley.
From left: Serenity Ibsen and Linden How at the Solheim Library Circulation Desk. Photo by Dan Kelley.
From left: Serenity Ibsen, Linden How, Kate Rubick at the Albert Solheim Library Circulation Desk. Photo by Dan Kelley.
Serenity Ibsen at the IT Help Desk, Albert Solheim Library. Photo by Dan Kelley.
Reference desk at the Albert Solheim Library. Photo by Dan Kelley.
View of the atrium space, the "Crumpacker Family Reading Room," from the mezzanine at the Albert Solheim Library. Photo by Dan Kelley.
PNCA has occupied the new campus since February 2015, but the library was not actually completed until summer 2015, so for the library staff, this has been the first academic year in their new space. When they first moved in, a large portion of the library was inaccessible unless you were wearing a hard hat! They had a service desk and could check out materials to students and faculty — even though most of their collections were located off-site at the old campus. Look for a piece — forthcoming in OLA Quarterly — by Library Assistant, Linden How and Sara Bystrom, Library Access Services Manager, on how they lived through the transition.
The final product was well worth the initial chaos. Natural light floods the atrium, with two-story ceilings and a wall of gorgeous original windows one one side juxtaposed with a cable-suspended concrete mezzanine balcony on the other. The effect of this mezzanine — a whole new floor in the restored historic building — is breathtaking. It gives the library a feeling of openness and chic Bohemian charm.
And it is extremely easy to find — just enter the building, turn left and walk in! It could not be any more prominently featured, and this is undeniably "one of the best things about our new space," according to Technical Services and Archives Librarian, Serenity Ibsen. Ibsen graciously showed me around around on a rainy afternoon (along with my Watzek Library colleague, Dan Kelley, who took the photos). She shared her thoughts about the new Albert Solheim Library and how it is being used.
There are two service points on opposite ends of the the first floor — the circulation desk and an IT Help Desk (a popular relocation of this service). In between is an atrium, called the Crumpacker Family Reading Room, furnished with high-backed privacy seating and arc reading lamps. There is also a cluster of workstations and a long counter space with plugins and a view out the windows. On the afternoon we visited, the reading chairs were empty, but there were people at the workstations and at the counter on laptops. Faculty and student art is on display, though one tradeoff of having so many high windows is that they have less wall-space than they did before for exhibits. Transparent sunshades prevent glare.
On the mezzanine level, there is a reference desk (the previous library did not have one), as well as several study rooms, which are heavily used. There is another long counter along the edge of the balcony, with a view of the windows and atrium. Much of the collection is also shelved on this floor. Ibsen told us that when the space first opened, there was one study nook with comfortable seating, but library staff felt this was insufficient. So they shifted the collection and took out several shelves to create two new nooks at either end of the balcony — one with an appealing turquoise sofa and grey chairs and another with two magenta upholstered chairs.
Mezzanine study nook in the Albert Solheim Library. Photo by Dan Kelley.
Mezzanine study nook at the Albert Solheim Library. Photo by Dan Kelley.
Graphic novels at the Albert Solheim Library. Photo by Dan Kelley.
Ibsen describes herself as a "nester" and says that when she uses libraries she always seeks out places to sit that are tucked away. She has observed that many PNCA students have similar preferences, and she says she has noticed another advantage of locating seating in the stacks. "They look up from what they are doing and something entices them. Then you see them pulling a book from the shelf." Of course, the PNCA Library has some very eye-catching books, including an extensive collection of graphic novels — shelved in close proximity to one of the nooks. Intermingling seating areas and and books helps facilitate contemplation and collision with collections. The addition of the two nooks on the mezzanine is a fine counterbalance to the more social space of the Crumpacker Family Reading Room.
One factor impacting the library space on the mezzanine it that there is no library elevator — only stairs. And since the mezzanine was added as a new floor, it is not serviced by the building's existing elevators. There is a freight elevator, but it is outside the library and not open to the public. So wheelchair access to the mezzanine involves staff intervention, which is hardly ideal. Ibsen says that they are hoping to be able to install an ADA lift inside the library to alleviate this issue. "We clearly have some accessibility issues and are working to implement solutions," she said. Working to reimagine older buildings comes with challenges like that. Other usability issues with the new building have been identified, and there is a community putting pressure on PNCA to make sure that these — and other grievances — are addressed. You can read an update on those grievances here.
The remodel was designed by renowned architect and Portland native, Brad Cloepfil of Allied Works Architecture. The building now occupied by PNCA was built as a federal post office, but also housed immigration and customs enforcement, U.S. Customs and other agencies over the years. The campus more than doubled in size in the new location, and so did the library. Linden How, sitting behind the circulation desk, said how much she loves the new space. "We have students who were used to the industrial look and feel of the old space and kind of miss it. But Ibsen was quick to add, "I don't miss it at all."
~ Kate Rubick, ACRL-OR Member at Large (2015-2017)
Instruction Services Librarian, Lewis & Clark College
rubick@lclark.edu
Filed under: library spaces, news |
« Interview with Nancy Hoover, Marylhurst University ACRL-OR Board Elections in Progress »
Stephanie Miller (@abcedmillered), on April 26, 2016 at 12:19 pm said:
The purple chairs are gorgeous! What a welcoming, yet modern, space.


text:
\section{Introduction}
\label{sect_intro}

The mass loss in late evolutionary stages of low- and intermediate-mass
stars ($1 \la M/\mbox{$M_{\sun}$} \la 8$), particularly in the red giant branch
(RGB) and asymptotic giant branch (AGB), is important
not only for the evolution of the star itself but also for the chemical
enrichment of the interstellar medium.
The mass loss in Mira-type stars in the AGB phase, which are characterized by
the large-amplitude pulsation with a variability amplitude of $\Delta V
\approx 6$~mag and a period of $\sim$1 year, has been observationally and
theoretically intensively studied.
However, normal (i.e., non-Mira-type)
M giants show variability amplitudes of $\Delta V$ =
1--2~mag, much smaller than those of Mira stars, without clear periodic variations.
They are classified as semi-regular or irregular variables.
Among the M stars listed in the General Catalog of Variable
Stars (GCVS) 4.2 (Samus et al. \cite{samus09}), there are 1987 stars
classified as semi-regular or irregular giants (denoted as SRA, SRB, SRD,
LB, and L in the catalog), in contrast to 1524 stars
classified as Mira variables (see, however, Lebzelter et
al. \cite{lebzelter95} for the uncertainty in the classification in the
GCVS).  There are also many semi-regular or irregular variables whose spectral
type is unknown in the catalog.
Therefore, normal M giants with small variability amplitudes
may outnumber Mira stars considerably.

Despite their small variability amplitudes and the absence of clear
periodicities, normal M giants are experiencing mass loss with
mass-loss rates comparable to those in (optically bright) Mira stars.
Normal M giants in the AGB phase show
mass-loss rates of $10^{-7}$--$10^{-6}$~\mbox{$M_{\sun}$~yr$^{-1}$}\ and expansion
velocities of 5--15~\mbox{km s$^{-1}$}\ (e.g., Gonzalez Delgado et al.
\cite{gonzalez_delgado03}; Winters et al. \cite{winters03};
De Beck et al. \cite{debeck10}).
There is also evidence of significant mass loss in RGB stars
with mass-loss rates up to $10^{-6}$~\mbox{$M_{\sun}$~yr$^{-1}$}\ near
the tip of the RGB (Origlia et al. \cite{origlia07}, \cite{origlia10};
Ita et al. \cite{ita07}).

The mass-loss rate (\mbox{$\dot{M}$}) and expansion velocity (\mbox{$\varv_{\rm exp}$}) of
our target, BK~Vir, are estimated to be $(1.5-4)\times10^{-7}$~\mbox{$M_{\sun}$~yr$^{-1}$}\
and 4--7.5~\mbox{km s$^{-1}$}, respectively
(Gonzalez Delgado et al. \cite{gonzalez_delgado03}; Winters et al.
\cite{winters03}), which are approximately the same as in the
prototypical Mira $o$~Cet with \mbox{$\dot{M}$}\ = $(1-8)\times 10^{-7}$~\mbox{$M_{\sun}$~yr$^{-1}$}\
and \mbox{$\varv_{\rm exp}$}\ = 1.5--7~\mbox{km s$^{-1}$} (Winters et al. \cite{winters03}).
This illustrates the importance of the contribution of normal M giants
to the chemical enrichment of the interstellar medium.

For understanding the mass-loss mechanism in red giant stars, it is
indispensable to probe the physical properties of the region between the
upper photosphere and the innermost part of the circumstellar envelope,
where the energy and momentum are expected to be deposited for the wind
acceleration.
It is now known from spectroscopy and high-spatial resolution observations
in the IR that there is a dense, warm ($\sim$1000--2000~K) molecular outer
atmosphere, the so-called MOLsphere,
extending to a few \mbox{$R_{\star}$}\ not only in Mira stars but also in normal K--M
giants with small variability amplitudes
(e.g., Tsuji et al. \cite{tsuji97}; Tsuji \cite{tsuji01};
Perrin et al. \cite{perrin04}; Ohnaka \cite{ohnaka04};
Ohnaka et al. \cite{ohnaka05}; Takami et al. \cite{takami09}).
This MOLsphere is considered to play an important role in
driving mass outflows.
In the case of Mira stars, the large-amplitude pulsation can fairly explain
the presence of the extended atmosphere
(e.g., Ohnaka et al. \cite{ohnaka06}; Wittkowski et al. \cite{wittkowski07},
\cite{wittkowski08}; Woodruff et al. \cite{woodruff09}).
However, the amplitudes of the stellar pulsation are much smaller
in normal K--M giants, and therefore, the origin of the MOLsphere
in these stars is by no means clear.
In addition to the MOLsphere, the detection of
UV emission lines as well as the H$\alpha$ line suggests the presence of
a chromosphere (e.g., Eaton \cite{eaton95};
Isabel P\'erez Mart\'inez et al. \cite{isabel_perez_martinez11} and
references therein).
This means that there are both hot and warm components in the outer
atmosphere of normal K--M giants, and
the spectral analyses of the CO lines in
the UV and IR support this picture (e.g., Wiedemann et al. \cite{wiedemann94};
McMurry \& Jordan \cite{mcmurry00}).

The multi-component nature of the outer atmosphere is a key to understanding
the mass-loss mechanism in red giants.
IR spectro-interferometry, which enables spatially resolved spectroscopy
of molecular or atomic spectral features with a spatial resolution much
higher than achieved with single-dish telescopes, is effective for probing
the physical properties of the outer atmosphere.
While Mira stars have been intensively studied by IR spectro-interferometry
as mentioned above, IR spectro-interferometric observations
of normal red giants are still very scarce.
Recently, Mart\'i-Vidal et al. (\cite{marti-vidal11}) have presented
near-IR spectro-interferometric observations of the M6/7 giant
RS~Cap in the CO first overtone bands and \mbox{H$_2$O}\ bands with a medium
spectral resolution of 1500 using VLTI/AMBER.
In this paper, we report on VLTI/AMBER observations of the M7
giant BK~Vir in the individual CO first overtone lines near 2.3~\mbox{$\mu$m}\
with a higher spectral resolution of 12000.
BK~Vir shows no peculiar features and, therefore, is a good representative
of normal M giants (its evolutionary status
is discussed in Sect.~\ref{subsect_param}).
It was selected also for technical reasons, such as the brightness and
angular size appropriate for AMBER observations.

The paper is organized as follows.  Our AMBER observations and data reduction
are described in Sect.~\ref{sect_obs}.  The observational results are
shown in Sect.~\ref{sect_res} followed by the modeling of the data
presented in Sect.~\ref{sect_modeling}.
The implications of the results of the modeling are discussed in
Sect.~\ref{sect_discuss}.
Conclusions are presented in Sect.~\ref{sect_concl}.

\section{Observations}
\label{sect_obs}

AMBER (Petrov et al. \cite{petrov07}) is the near-IR (1.3---2.4~\mbox{$\mu$m})
spectro-interferometric instrument at VLTI.  It enables us to obtain
information on the amplitude and phase of the complex Fourier transform
of the object's intensity distribution with a
spectral resolution of up to 12000 by combining three 8.2~m Unit Telescopes
(UTs) or 1.8~m Auxiliary Telescopes (ATs).
AMBER measures several quantities related to the complex Fourier transform of
the object's intensity distribution: visibility, differential phase (DP), and
closure phase (CP).
The visibility (or also called visibility amplitude) contains information
about the size and shape of the object.
The DP can measure the deviation of the object's phase in a spectral
feature from that in the continuum, and non-zero DP within a spectral feature
means that the spectral feature-forming region is asymmetric.
The CP is the sum of the measured phases around a closed triangle of baselines.
The CP is always zero or $\pi$ for point-symmetric objects, and
non-zero and non-$\pi$ CPs indicate an asymmetry in the object.

BK~Vir was observed at 3 epochs between January and April 2009 with
AMBER using the E0-G0-H0 telescope configuration with ATs,
as summarized in Table~\ref{obslog}.
We used the high-spectral resolution mode in the $K$ band (\mbox{HR\_K})
with a spectral resolution of 12000
in the wavelength range between 2.26 and 2.31~\mbox{$\mu$m}, which includes
the CO (2,0) band head at 2.294~\mbox{$\mu$m}.  The VLTI fringe-tracker
FINITO was used to stabilize the fringes for a Detector Integration Time
(DIT) of 6~s.  This long DIT was necessary to achieve reasonable SNRs
in the CO lines, where the correlated flux (i.e., flux $\times$
visibility amplitude) is very low.

We reduced the data with amdlib
ver2.2\footnote{Available at http://www.jmmc.fr/data\_processing\_amber.htm}.
We took the best 80\% of the frames in terms of the fringe SNR
(Tatulli et al. \cite{tatulli07}).
The interferometric calibrators ($\nu$~Hya and $\beta$~Crv) were observed
just before and/or after BK~Vir.  We adopted angular diameters of 3.40 and
4.45~mas for $\nu$~Hya and $\beta$~Crv, respectively (Richichi \& Perschron
\cite{richichi05}).
The errors of the calibrated visibilities, DPs, and CPs were
estimated as described in Ohnaka et al. (\cite{ohnaka09}).

The AMBER data taken in \mbox{HR\_K}\ mode before December 2009 are affected by
the Fabry-Perot effect originating in the dichroics of the InfraRed
Image Sensor (IRIS), which stabilizes the image motion
\footnote{AMBER data taken after the
replacement of the IRIS dichroics in December 2009 do not show this effect
any more.}.
This effect appears as time-dependent, high-frequency beating in raw
visibilities, DPs, and CPs, when plotted as a function of
wavelength.  Fortunately, this effect is mostly removed by using the
calibrators observed just before and/or after the science target,
although the residual of this effect appears as the small-amplitude
beating in some cases (as seen in the observed CP at wavelengths below
2.293~\mbox{$\mu$m}\ in Fig.~\ref{obsres}e).

The long DIT of 6~s makes the absolute calibration of the observed
visibilities uncertain, because we cannot know the fraction of time during
DIT when the fringes were lost, and the fringe tracking may work differently
for the science target and the calibrator.
Therefore, we took the following approach for the absolute calibration of
the observed visibilities.
We note that the $K$-band uniform-disk diameters of BK~Vir reported in
the literature show little time variation within the measurement errors:
$11.2 \pm 0.6$~mas (Dyck et al. \cite{dyck98}), $10.73 \pm 0.23$~mas
(Perrin et al. \cite{perrin98}), and $11.49 \pm 0.40$~mas (Perrin et al.
\cite{perrin03}).
In the present work, we adopted a uniform-disk diameter of 10.73~mas,
which has the smallest error among the above measurements.
We scaled the observed calibrated visibilities in the continuum to
those expected from the uniform disk with an angular diameter of 10.73~mas.

The wavelength calibration was carried out using the telluric lines
identified in the spectra of the calibrators.
As a template of the telluric lines, we convolved the atmospheric transmission
spectrum measured at the Kitt Peak National
Observatory\footnote{http://www.eso.org/sci/facilities/paranal/instruments/isaac/tools/\\spectra/atmos\_S\_K.fits}
to match the spectral resolution of AMBER.
The uncertainty in wavelength calibration is $4 \times 10^{-5}$~\mbox{$\mu$m}\
($\sim$5.2~\mbox{km s$^{-1}$}).
The wavelength scale was converted to the laboratory frame using a
heliocentric velocity of 16.5~\mbox{km s$^{-1}$}\ measured for BK~Vir
(Gontcharov \cite{gontcharov06}; Famaey et al. \cite{famaey05}).

Since no spectroscopic standard star was observed, we used the interferometric
calibrators for the spectroscopic calibration to remove the telluric lines
from the observed spectrum of BK~Vir.
However, both $\beta$~Crv (G5II) and $\nu$~Hya (K0/K1III) show CO absorption
lines.
In this case, the calibrated spectrum of the science target is
derived as
$F_{\star}^{\rm sci} = F_{\rm obs}^{\rm sci} / (F_{\rm obs}^{\rm
  cal}/F_{\star}^{\rm cal})$,
where $F_{\star}^{\rm sci(cal)}$ and $F_{\rm obs}^{\rm sci(cal)}$ denote
the true and observed (i.e., including the atmospheric transmission
and the detector's response) spectra of the science target
(or calibrator), respectively.
To estimate the true spectrum of $\nu$~Hya, we used the high-resolution
$K$-band spectrum of $\alpha$~Boo (K1III) obtained by Wallace \& Hinkle
(\cite{wallace96}), which has a similar spectral type to $\nu$ Hya.
The spectrum of $\alpha$~Boo, which has a spectral resolution of 89000,
was convolved down to match the resolution of AMBER.  This convolved
spectrum of $\alpha$~Boo reproduces the strength of the CO band
head observed in $\nu$~Hya,
indicating that it can be used as the true spectrum of $\nu$~Hya.

For $\beta$~Crv, however, no high-resolution CO spectra of stars with similar
spectral types are available in the literature.  Therefore,
we estimated the true spectrum for $\beta$~Crv by constructing a model CO
spectrum using the MARCS models (Gustafsson et al. \cite{gustafsson08}).
The MARCS models
represent spherically symmetric photospheres with molecular and atomic
line opacities taken into account using the opacity sampling method.
Each MARCS model is specified by effective temperature (\mbox{$T_{\rm eff}$}),
surface gravity ($\varg$), microturbulent velocity (\mbox{$\varv_{\rm micro}$}),
chemical composition, and stellar mass ($M_{\star}$).
These parameters derived for $\beta$~Crv are  \mbox{$T_{\rm eff}$}\ = 5100--5145~K,
$\log \varg$ = 2.2--2.7 (given in units of cm~s$^{-2}$ throughout the paper),
\mbox{$\varv_{\rm micro}$}\ = 1.5--2.1~\mbox{km s$^{-1}$}, and 3.0--3.7~\mbox{$M_{\sun}$}\ (Luck et al. \cite{luck95};
Takeda et al. \cite{takeda08}; Lyubimkov et al. \cite{lyubimkov10}).
The CNO abundances derived by Luck et al. (\cite{luck95}) suggest the mixing
of CN-cycled material.
We selected a model atmosphere with parameters as close to these
values as possible from the MARCS model grid\footnote{http://marcs.astro.uu.se}.
The selected model is characterized with \mbox{$T_{\rm eff}$}\ = 5250~K, $\log \varg$ = 2.5,
$\mbox{$\varv_{\rm micro}$}$ = 2~\mbox{km s$^{-1}$}, $M_{\star}$ = 1~\mbox{$M_{\sun}$}, and ``moderately CN-cycled''
chemical composition with C/N = 1.5.
The stellar mass of this model is smaller than the observationally
estimated values above.  However, the atmosphere is approximately
plane-parallel with a geometrical thickness of $\sim$1\% of the
stellar radius.  In this case, the stellar mass does not affect the
atmospheric structure noticeably.
Using the temperature and pressure distributions of this model, we
computed a synthetic spectrum for the CO first overtone lines
using the line list of Goorvitch (\cite{goorvitch94}).
The carbon abundance was adjusted to fit the CO band head in the
uncalibrated spectrum of $\beta$~Crv.
With $F_{\star}^{\rm cal}$ constructed in this fashion,
the calibrated spectrum of BK~Vir was derived using the above
equation.
Although the strengths of the CO lines in two calibrators are
very different (the line depths are 20--30\% and 10\% for $\nu$~Hya
and $\beta$~Crv, respectively), the spectra of BK~Vir calibrated with
these stars agree well (see Fig.~\ref{tempvar}a, where both spectra
calibrated with $\nu$~Hya (2009 Feb 28) and $\beta$~Crv (2009 Apr 15)
are shown).  This indicates that the calibrated CO line spectra of
BK~Vir are not significantly affected by the above, unusual spectroscopic
calibration.

\begin{figure*}
\resizebox{\hsize}{!}{\rotatebox{-90}{\includegraphics{18128F1.ps}}}
\caption{AMBER data of BK~Vir (data set \#3).
In each panel, the scaled observed spectrum is plotted by the black solid
lines.
{\bf a})--{\bf c}) Visibilities observed on the 15.9, 31.8, and 47.8~m
baselines (red lines).  The corresponding spatial resolutions are also given.
{\bf d}) Uniform-disk diameter (red line) derived by fitting the visibilities
shown in the panels {\bf a})--{\bf c}).
{\bf e})--{\bf g}) Differential phases observed on the 15.9, 31.8, and
47.8~m baselines (red lines).
{\bf h}) Closure phase (red line). }
\label{obsres}
\end{figure*}

\section{Results}
\label{sect_res}

Figure~\ref{obsres} shows the observed visibilities, DPs, CPs, and spectrum
from the data set \#3.
The results from the other data sets are similar, and therefore, not shown.
The figure reveals significant signatures of the CO lines in the observed
visibilities, DPs, and CPs.
Thanks to the long DIT of 6~s, the visibilities as low as 0.01 could be
measured in the CO lines.
As plotted in Fig.~\ref{obsres}d,
the uniform-disk diameter obtained from the observed visibilities shows
that the star appears larger in the CO lines (12--14~mas) than in the
continuum (10.73~mas) by 12--31\%.
However, the uniform-disk fit in the CO lines is poor with
reduced $\chi^2$ values much higher than 1 (as high as $10^2$--$10^3$),
which means
that the uniform disk is a poor representation of the object's shape
in the CO lines.  Therefore, the uniform-disk diameter in the CO lines
should be regarded as a very rough estimate of the characteristic size
of the object.

Figures~\ref{obsres}e--\ref{obsres}h show the detection of non-zero DPs
(particularly clear on the 47.8~m baseline) and non-zero/non-$\pi$
CPs in the CO lines, which indicate an asymmetry in the CO line-forming
region.
High-spatial resolution observations have revealed that
asymmetries in the atmosphere of red giant stars are common.
The images of the Mira star R~Cas in the TiO bands obtained by
Weigelt et al. (\cite{weigelt96}) show elongation, while the image in the
continuum appears circular.
The optical images of the prototypical Mira star $o$~Cet taken with
the Hubble Space Telescope show significant asymmetries (Karovska
et al. \cite{karovska97}).
Tuthill et al. (\cite{tuthill99}) also revealed departures from
circular symmetry in five Mira
stars (including the above two stars) in the optical and near-IR.
The aperture synthesis images of the Mira stars R~Aqr and U~Ori in the
$H$ band obtained with the Infrared Optical Telescope Array (IOTA) show
asymmetric, extended atmospheres (Ragland et al. \cite{ragland08};
Pluzhnik et al. \cite{pluzhnik09}).
U~Ori shows asymmetry in the $K$ band as well (Mondal \& Chandrasekhar
\cite{mondal04}).
There are more stars for which asymmetries are indicated from the
detection of non-zero CPs.
Bedding et al. (\cite{bedding97}) detected non-zero CPs for the
Mira-like star R~Dor.
Ragland et al. (\cite{ragland06}) also report asymmetries
in a sample of AGB stars based on the detection of non-zero CPs.
More recently, Wittkowski et al. (\cite{wittkowski11}) have shown
asymmetries in the CO first overtone bands in Mira stars
by AMBER observations with a spectral resolution of 1500.
Our AMBER observations are the first study to detect asymmetry in
a red giant star in the individual CO lines.

Figure~\ref{obsresCO}a, which shows an enlarged view of the visibilities
in four representative CO lines obtained on the 47.8~m baseline,
reveals that
the observed visibilities are approximately symmetric with respect to the
line center.
On the other hand, Fig.~\ref{obsresCO}b shows
the visibility of the red supergiant Betelgeuse observed on the 11.54~m
baseline  (data set \#5 of Ohnaka et al. \cite{ohnaka11}).
Because the angular diameter of Betelgeuse (42.5~mas, Ohnaka et al.
\cite{ohnaka11}) is four times larger than that of BK~Vir (10.73~mas),
the 11.54~m baseline for Betelgeuse probes nearly the same
spatial scale in terms of the stellar angular diameter
as the 47.8~m baseline for BK~Vir (0.9 $\times$ stellar
angular diameter).
Figure~\ref{obsresCO}b clearly shows that the observed visibilities are
asymmetric with respect to the line center in the case of Betelgeuse:
the visibilities are characterized by the minima in the blue wing and
the maxima in the red wing.
These asymmetric visibilities are interpreted
as temporally variable, inhomogeneous gas motions within 1.3--1.4~\mbox{$R_{\star}$}\
over the stellar surface
with velocity amplitudes of up to 20--30~\mbox{km s$^{-1}$}\ (Ohnaka et al. \cite{ohnaka09},
\cite{ohnaka11}).
The absence of such asymmetric visibilities in
BK~Vir suggests that the amplitude of the inhomogeneous velocity field is
much smaller than the AMBER's spectral resolution of 12000, say, $\sim$5~\mbox{km s$^{-1}$},
and/or the spatial scale of the inhomogeneous gas motions is much smaller
than the spatial resolution of the current AMBER data (9.8~mas).
However, the former possibility is more favorable, because
the non-zero DPs and non-zero/non-$\pi$ CPs shown in Fig.~\ref{obsres}
indicate that the inhomogeneity is spatially resolved with the current
spatial resolution.

We examined time variation using the AMBER data taken at nearly the same
$uv$ points.
The shortest and middle baselines of the data sets taken on 2009 Feb 28
and 2009 Apr 15 are almost the same (the 1~m difference in the longest
baseline is too significant to study time variations).
A comparison between these two data sets is shown in
Fig.~\ref{tempvar}.
The sampled wavelengths are slightly different for
the two nights because of the difference in the correction to convert
the observed wavelength scale to the heliocentric scale.
Figures~\ref{tempvar}a and \ref{tempvar}c show that the observed spectra and
the visibilities on the 32~m baseline
measured on the two nights form continuous curves, suggesting no time
variation.  This is also the case for the 16~m visibility shown in
Fig.~\ref{tempvar}b except for the CO band head at 2.2936~\mbox{$\mu$m},
where the visibility measured on Apr 15 is 12--20\% lower than that
measured on Feb 28.
This suggests possible time variation on a spatial scale of 30~mas
(3 $\times$ stellar diameter).
The decrease in the visibility corresponds to an increase in the
uniform-disk diameter by 22\% (from 16 to 19.5~mas) or an increase in
the Gaussian FWHM by 14\% (from 10.5 to 12~mas) between Feb 28 and
Apr 15.
However, the difference is within 3-$\sigma$ of the data from Feb 28.
Therefore, more observations are needed to definitively confirm time
variations in the visibility.

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F2.ps}}}
\caption{Visibilities in four representative CO first overtone lines in the
red giant BK~Vir (panel {\bf a}) and the red supergiant Betelgeuse
(panel {\bf b}).
In both panels, the black solid lines represent the scaled observed spectra.
The red solid lines represent the visibility obtained for BK~Vir
on the 47.8~m baseline (panel {\bf a}) and that obtained for Betelgeuse
on the 11.54~m baseline (panel {\bf b}).  }
\label{obsresCO}
\end{figure}

\section{Modeling of the AMBER data}
\label{sect_modeling}

\subsection{Determination of stellar parameters}
\label{subsect_param}

To interpret the AMBER observations, we use the MARCS models.
As mentioned in Sect.~\ref{sect_obs}, these models assume spherical
symmetry.
Whereas the asymmetry in the CO-line-forming region is detected,
we use these spherical models as the first approximation.
To select a MARCS model appropriate for BK~Vir, we determined
its stellar parameters (\mbox{$T_{\rm eff}$}, $\varg$, \mbox{$\varv_{\rm micro}$}, $M_{\star}$, and chemical
composition) as follows.

We estimated the effective temperature from the observed angular
diameter and the bolometric
flux obtained by integrating the photometric data available in the
literature
(Two-Micron Sky Survey, Neugebauer \& Leighton \cite{neugebauer69};
NOMAD Catalog, Zacharias et al. \cite{zacharias04};
2MASS, Skrutskie et al. \cite{skrutskie06};
Fouque et al. \cite{fouque92};
Kerschbaum \& Hron \cite{kerschbaum94};
IRAS Point Source Catalog).
The photometric data were corrected for the interstellar extinction
using $E(B-V)$ = 0.023 (Schlegel et al. \cite{schlegel98}) and
assuming $A_{V} = 3.1 E(B-V)$.
Combining the angular diameter of $10.73$~mas adopted in
Sect.~\ref{sect_obs}
and a derived bolometric flux of $2.80 \times 10^{-9}$~\mbox{$\rm W m^{-2}$}
results in an effective temperature of $2920$~K.
While this agrees with the effective temperature of $3074 \pm 141$~K
derived by Dyck et al. (\cite{dyck98}), they obtained a higher bolometric flux
of $3.9 \times 10^{-9}$~\mbox{$\rm W m^{-2}$}.
If we adopt, as the uncertainty in the bolometric flux,
a half of the difference between the values from Dyck et al. (\cite{dyck98})
and from the present work, the total error (i.e., error resulting from
the uncertainties in the angular diameter and in the bolometric flux)
in our effective temperature is $\pm 150$~K.
Using the distance of 180~pc based on the Hipparcos parallax of
$5.53 \pm 0.68$~mas (van Leeuwen \cite{vanleeuwen07}) and the above
bolometric flux of $2.80 \times 10^{-9}$~\mbox{$\rm W m^{-2}$}, we derived
a luminosity of 2700~\mbox{$L_{\sun}$}\ (\mbox{$M_{\rm BOL}$}\ = $-3.8$).  With the error in the
parallax and the above error in the bolometric flux,
the total uncertainty in the luminosity is $\pm 850$~\mbox{$L_{\sun}$}.

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F3.ps}}}
\caption{Spectra (panel {\bf a}) and visibilities (panels {\bf b}: 16~m
baseline and {\bf c}: 32~m baseline) obtained on 2009 Feb 28 and 2009 Apr
15.
In all panels, the data taken on 2009 Feb 28 and 2009 Apr 15 are plotted
by the black and red dots, respectively.
}
\label{tempvar}
\end{figure}

To estimate the stellar mass, we compared the position of BK~Vir on the
H-R diagram with theoretical evolutionary tracks.
Figure~\ref{hr_diagram} shows evolutionary tracks for 1 and 2~\mbox{$M_{\sun}$}\ stars
(Herwig \cite{herwig05}\footnote{http://astrowww.phys.uvic.ca/\textasciitilde
  fherwig} and Bertelli et al. \cite{bertelli08}, respectively),
together with the observationally derived position of BK~Vir.
The figure suggests that the mass of BK~Vir is close to 1~\mbox{$M_{\sun}$}.
The adoption of a stellar mass of 1~\mbox{$M_{\sun}$}\ translates into a surface
gravity of $\log \varg = -0.17$ with a stellar radius of 201~\mbox{$R_{\sun}$}\ (0.94~AU).

Whereas BK~Vir is classified as an AGB star in most of the literature,
Fig.~\ref{hr_diagram} shows that the luminosity of BK~Vir is just at the tip
of the RGB.
Moreover, Lebzelter \& Hron (\cite{lebzelter99}) report negative detection
of $^{99}$Tc, which would be strong evidence of the third dredge-up in the
AGB.  Therefore, we cannot conclude whether BK~Vir is an RGB star or an
early-AGB star that has not yet experienced the third dredge-up.
In either case, however, the surface chemical composition is
expected to be changed by the first dredge-up in the RGB phase, which
mixes the CN-cycled material to the stellar surface.
This makes the MARCS models with the ``moderately CN-cycled'' chemical
composition (with [Fe/H] = 0.0) suitable for BK~Vir.

No analysis of the micro-turbulent velocity in BK~Vir is available in the
literature.  However, the high-resolution spectroscopic analysis of M7--8
giants with $\mbox{$T_{\rm eff}$} \la 3000$~K by Tsuji (\cite{tsuji08}) shows micro-turbulent
velocities of 3--4~\mbox{km s$^{-1}$}.  We adopt these values for BK~Vir as well.

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F4.ps}}}
\caption{Observationally derived position of BK~Vir on the H-R diagram
(green dot with the error bars).
The solid line and open triangles represent the evolutionary tracks
for a 1 and 2~\mbox{$M_{\sun}$}\ star from Herwig (\cite{herwig05}) and Bertelli et al.
(\cite{bertelli08}), respectively.
The AGB stage (early AGB and thermally-pulsing AGB) is marked in blue and
red for the evolutionary tracks for 1~\mbox{$M_{\sun}$}\ and 2~\mbox{$M_{\sun}$}, respectively.
}
\label{hr_diagram}
\end{figure}

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F5.ps}}}
\caption{
Comparison between the observed interferometric data (data set \#3)
and the MARCS model.
In all panels, the black thin lines represent the predictions of the MARCS
model with the parameters most appropriate for BK~Vir (see
Sect.~\ref{subsect_marcs}).  The thick colored lines represent the observed
data.
{\bf a}) Spectrum.  Residuals of the strong telluric lines are marked
by $\oplus$.
{\bf b})--{\bf d}) Visibilities on the 15.9, 31.8, and 47.8~m baselines,
respectively.
{\bf e}) Closure phase.
}
\label{marcs3000}
\end{figure}

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F6.ps}}}
\caption{
MARCS model for BK~Vir.
{\bf a}) Model spectrum near the CO band head.  The black, red, and blue
dots represent the wavelengths of the intensity profiles and visibilities
shown in the panels {\bf b} and {\bf c}.
{\bf b}) Model intensity profiles for the continuum (black), CO band
head (red) and an isolated CO line (blue).
{\bf c}) Model visibilities for the continuum, CO band head, and an
isolated CO line are shown by the black, red, and blue solid lines,
respectively.
The filled symbols represent the observed visibilities
(data set \#3) at the corresponding wavelengths.
}
\label{clvvisplot_marcs3000}
\end{figure}

\subsection{Comparison with the MARCS photospheric model}
\label{subsect_marcs}

The MARCS model with the parameters
as close to the derived values as possible is characterized by
\mbox{$T_{\rm eff}$}\ = 3000~K, $\log \varg$ = 0.0, $M_{\star}$ = 1~\mbox{$M_{\sun}$}, \mbox{$\varv_{\rm micro}$}\ = 2~\mbox{km s$^{-1}$}\
(models with \mbox{$\varv_{\rm micro}$}\ = 3--4~\mbox{km s$^{-1}$}\ are not available for this combination
of \mbox{$T_{\rm eff}$}, $\log \varg$, $M_{\star}$, and chemical composition, and the model
with \mbox{$\varv_{\rm micro}$}\ = 2~\mbox{km s$^{-1}$}\ is the closest one).
Using the temperature and pressure distributions of the downloaded MARCS
model, we computed the monochromatic intensity profile and spectrum over
the observed wavelength range using the CO line list of Goorvitch
(\cite{goorvitch94}), as described in Ohnaka et al. (\cite{ohnaka06}).
The monochromatic visibility was calculated by the Fourier transform
of the monochromatic intensity profile.
The intensity profile, visibility, and spectrum were then convolved with
the AMBER's spectral resolution.
The angular scale of the model was determined so that the uniform-disk
diameter derived from the model visibilities in the continuum matches
the adopted value of 10.73~mas.

Figure~\ref{marcs3000} shows a comparison between the observed data
(data set \#3) and the predictions
by the MARCS photospheric model.  While the observed CO spectrum is well
reproduced, the predicted visibilities in the CO lines are too
high compared to the observed data.
We also used other available MARCS models with slightly different stellar
parameters (\mbox{$T_{\rm eff}$}\ = 2700--3100~K, \mbox{$\log \varg$}\ = $-0.5$ -- $+0.5$, $M_{\star}$ =
1--2~\mbox{$M_{\sun}$}, and \mbox{$\varv_{\rm micro}$}\ = 2--5~\mbox{km s$^{-1}$}), but
they cannot reproduce the observed visibilities in the CO lines, either.
Figure~\ref{clvvisplot_marcs3000} shows the intensity profiles and
visibilities at three representative wavelengths in the continuum,
at the CO band head, and in an isolated line.
The figure illustrates that the photosphere extends to 1.17~\mbox{$R_{\star}$}\
in the CO band head and in the isolated line,
but this geometrical extension is insufficient to
explain the observed visibilities (Fig.~\ref{clvvisplot_marcs3000}c).
The too high visibilities in the CO lines predicted by the MARCS model
means the actual CO-line-forming layer is much more extended than
the model predicts or there is an additional component
contributing to the CO lines above the photosphere modeled by MARCS.
Therefore, our AMBER observations have spatially resolved the MOLsphere
in a normal M giant for the first time in the individual CO lines.
The same trend was reported for the normal M6-7 giant RS~Cap
by Mart\'{i}-Vidal et al. (\cite{marti-vidal11}) based on AMBER observations
of the CO bands with a lower spectral resolution of 1500.
These studies illustrate that testing photospheric models only with
the spectra of strong molecular or atomic features can be misleading.

\begin{table*}
\begin{center}
\caption {Parameters of the MARCS+MOLsphere model for BK~Vir}
\vspace*{-2mm}

\begin{tabular}{l l l}\hline
Parameter &  Searched range &  Solution \\
\hline
CO column density of the inner layer: $N_{\rm inner}$ (\mbox{cm$^{-2}$}) &
$10^{21}, 2\times10^{21}, 5\times10^{21}, 10^{22}, ...,
10^{23}$ & (1--2)$\times10^{22}$ \\
CO column density of the outer layer: $N_{\rm outer}$ (\mbox{cm$^{-2}$}) &
$5\times10^{18}, 10^{19}, 2\times10^{19}, 5\times10^{19},
..., 5\times10^{20}$ & $10^{19}$--$10^{20}$ \\
Temperature of the inner layer: $T_{\rm inner}$ (K) &
1800 ... 2300 ($\Delta T_{\rm inner}$ = 100~K) & 1900--2100\\
Temperature of the outer layer: $T_{\rm outer}$ (K) &
1200 ... 2300 ($\Delta T_{\rm outer}$ = 100~K) & 1500--2100\\
Radius the inner layer: $R_{\rm inner}$ (\mbox{$R_{\star}$}) &
1.2, 1.25, 1.3 & 1.2--1.25\\
Radius the outer layer: $R_{\rm outer}$ (\mbox{$R_{\star}$}) &
1.5, ..., 3.5 ($\Delta R_{\rm outer}$ = 0.5~\mbox{$R_{\star}$}) & 2.5--3.0\\
\hline
\label{table_param}
\vspace*{-7mm}

\end{tabular}
\end{center}
\end{table*}

\subsection{Modeling of the MOLsphere}
\label{subsect_wme}

To characterize the physical properties of the MOLsphere,
we interpreted the AMBER data with a model in which one or
two extended CO layers with constant temperatures and densities
are added above the MARCS photospheric model.
This model is the same as that described in Ohnaka (\cite{ohnaka04}),
but with the following modification:
each layer is assumed to be geometrically thin with a thickness of
0.1~\mbox{$R_{\star}$}.  The inner radius of each layer is used as the parameter to
represent the size of the layer.
The radius, temperature,
and column density of each layer are changed as free parameters to
fit the observed spectrum and visibilities simultaneously.
We tentatively adopted a microturbulent velocity of 4~\mbox{km s$^{-1}$}\ for the
CO layers based on the spectroscopic analysis of Tsuji (\cite{tsuji08})
for M7--8 giants.
We first attempted to explain the observed data with models with one
additional CO layer but could not reproduce the spectrum and visibilities
simultaneously.
Therefore, we attempted to explain the data with the models with two CO
layers.
Table~\ref{table_param} gives the range of the parameters
searched in our modeling.  Note that the radius of the inner layer
was set to be equal to or larger than 1.2~\mbox{$R_{\star}$}\ to avoid an overlap
with the MARCS photospheric model, which extends to 1.17~\mbox{$R_{\star}$}.

Figure~\ref{marcs3000_wme_final} shows a comparison between the observed data
(data set \#3) and the best-fit model.
The model intensity profiles and visibilities at three representative
wavelengths (continuum, CO band head, and isolated CO line) are plotted
in Fig.~\ref{clvvisplot}.
This model is characterized by the inner CO layer at 1.2~\mbox{$R_{\star}$}\ with
2000~K and a CO column density of $2\times10^{22}$~\mbox{cm$^{-2}$}\ and the outer CO
layer at 2.5~\mbox{$R_{\star}$}\ with 1900~K and a column density of $2\times10^{19}$~\mbox{cm$^{-2}$}.
The column densities of the inner and outer CO layer correspond to
16\% and 0.016\% of the CO column density in the MARCS photospheric model.
We found the range of the radius, temperature and CO column density
of the inner layer to be 1.2--1.25~\mbox{$R_{\star}$}, 1900--2100~K, and
(1--2)$\times10^{22}$~\mbox{cm$^{-2}$}, respectively.
The derived ranges for the radius, temperature, and CO column density
of the outer layer are 2.5--3.0~\mbox{$R_{\star}$}, 1500--2100~K, and
$10^{19}$--$10^{20}$~\mbox{cm$^{-2}$}, respectively.
As shown in Fig.~\ref{marcs3000_wme_final},
the observed visibilities and spectrum are well reproduced.
The model also predicts the CP to jump in the CO lines, in particular at the
CO band head, as seen in the AMBER data.
This can be explained as follows.  Figure~\ref{clvvisplot}b shows that
the inner CO layer, which is optically thick, makes the star appear larger
in the CO band head than in the continuum by 30\%.  Then the
longest baseline samples the second visibility lobe in the CO band
head, as shown in Fig.~\ref{clvvisplot}c (red line and red triangle at
a spatial frequency of $\sim$100~arcsec$^{-1}$).
The phase in the second visibility lobe is $\pi$, while the phases
on the shortest and middle baselines in the first visibility lobe are zero.
This results in a predicted CP of $\pi$ for the CO band head and
leads to the jumps in the CP as observed.
Because the model is spherically symmetric,
the observed non-zero/non-$\pi$ CPs and non-zero DPs are not
reproduced\footnote{The model DPs for the shortest and middle baselines
are zero, and the model DP for the longest baseline is the same as the
model CP with its sign flipped.}.
However, the overall agreement in the spectrum, visibilities, and CP
suggests that our model represents the approximate picture of the outer
atmosphere of BK~Vir.

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F7.ps}}}
\caption{
Comparison between the observed interferometric data and the MARCS+MOLsphere
model shown in the same manner as Fig.~\ref{marcs3000}.
}
\label{marcs3000_wme_final}
\end{figure}

It is impossible to uniquely constrain the detected inhomogeneous
structure from our observations.  However, we estimated the flux contribution
of asymmetric features from the observed CPs as follows.
We added a Gaussian-shaped spot to the best-fit model image in the CO lines
and computed the visibility and CP at the observed baselines.
We changed the size and intensity of the Gaussian-shaped spot so that
the observed non-zero/non-$\pi$ CPs (40--100\degr) can be
reproduced without affecting the fit to the observed visibilities
significantly.
This experiment suggests that the flux contribution of the asymmetric
feature is 3--5\% of the total flux.
These values agree with those estimated for other AGB stars.
Ragland et al. (\cite{ragland06}) derived a flux
contribution of 3\% from a geometrical modeling (uniform disk +
unresolved spot) of the asymmetric features detected in a sample of AGB
stars in the $H$-broadband.
Wittkowski et al. (\cite{wittkowski11}) also suggest a flux contribution
of up to $\sim$3\% in the 2~\mbox{$\mu$m}\ \mbox{H$_2$O}\ band for the Mira star R~Cnc.

The observed spectrum is nearly equally well reproduced by the
MARCS-only model and MARCS+MOLsphere model, despite the clear
disagreement between the observed visibilities and MARCS-only model.
The reason is that the additional absorption due to the CO layers above the
MARCS model is filled in by the extended emission of the same
CO layers in the spatially unresolved spectrum.  Therefore, good agreement
between observation and model for spatially unresolved spectra of strong
molecular features can be misleading, because these features can include
the contribution from the extended outer atmosphere.

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{0}{\includegraphics{18128F8.ps}}}
\caption{
MARCS+MOLsphere model for BK~Vir shown in the same manner as
Fig.~\ref{clvvisplot_marcs3000}.
}
\label{clvvisplot}
\end{figure}

\section{Discussion}
\label{sect_discuss}

Figure~\ref{plotTemp} shows the temperature distribution of the MARCS
photospheric model as a function of radius, together with the location and
the temperature of
the extended CO layers derived from our modeling.  The temperature of the
inner CO layer is noticeably higher than that of the uppermost layer of the
MARCS photospheric model, although the height is approximately the same.
The temperature of the outer CO layer is also
higher than or equal to that of the top of the photosphere.
This suggests a temperature inversion in the MOLsphere of BK~Vir.

Given that our spectroscopic calibration method without a usual spectroscopic
standard star gives the reliable CO line spectra of BK~Vir as described in
Sect.~\ref{sect_obs}, the uncertainty in the spectra are unlikely to affect
the result of our modeling.

We checked whether this is merely a result of approximating the
temperature distribution in the outer atmosphere by two discrete layers.
We set the temperatures of the CO layers to be below 1500~K, which is the
temperature of the uppermost layer of the MARCS photospheric model,
and attempted to reproduce the observed data.  However, it turned out that
such models cannot provide a reasonable fit to the observed spectrum and
visibilities simultaneously.
Therefore,
the temperature inversion suggested in Fig.~\ref{plotTemp} is unlikely
to be a result of the simplification we adopted for the structure of the
outer atmosphere.

\begin{figure}
\resizebox{\hsize}{!}{\rotatebox{-90}{\includegraphics{18128F9.ps}}}
\caption{
Temperature distribution as a function of radius.  The black solid line
represents the temperature profile of the MARCS model used for BK~Vir.
The red and blue rectangles represent the ranges of the inner and outer
CO layers derived from our modeling, respectively.
}
\label{plotTemp}
\end{figure}

We also checked whether or not the assumption of local thermodynamical
equilibrium (LTE) used in our model is valid for the CO layers.
As described in Ohnaka (\cite{ohnaka04}),
we compared the collisional and radiative
de-excitation rates.  The collisional de-excitation rate $C_{\rm ul}$ is
estimated as $N \, \sigma_{\rm ul} \,\varv_{\rm rel}$, where $N$ is the number
density of the primary collision partner, $\sigma_{\rm ul}$ is the cross
section, which is approximated with the geometrical cross section, and
$\varv_{\rm rel}$ is the relative velocity between the collision partner
and CO molecules.  The CO column density of $10^{21}$~\mbox{cm$^{-2}$}\ derived
for the inner layer and the layer's geometrical thickness of 0.1~\mbox{$R_{\star}$}\
translates into a CO number density of $7 \times 10^{9}$~\mbox{cm$^{-3}$}.
In chemical equilibrium at the temperature of 2000~K derived for the inner
layer, number densities of H atoms and H$_2$ molecules of $1.2\times10^{13}$
and $1.4\times10^{13}$~\mbox{cm$^{-3}$}\ are necessary to obtain the
above CO number density.  We take both H atoms and H$_2$ molecules as the
primary collision partner of CO molecules, which leads to $N = 2.6 \times
10^{13}$~\mbox{cm$^{-3}$}.  With a geometrical cross section $\sigma_{\rm ul}$ of
$10^{-15}$~\mbox{cm$^{-2}$}\ and a relative velocity $\varv_{\rm rel}$ of 5~\mbox{km s$^{-1}$}
assumed, we obtain $C_{\rm ul} = 1.3\times10^{4}$~s$^{-1}$ for the inner
CO layer.
In the case of the outer CO layer,
the lower limit of the CO column density ($10^{19}$~\mbox{cm$^{-2}$}) translates into
a CO number density of $7.1\times10^{6}$~\mbox{cm$^{-3}$}.
For the temperatures of 1500--2100~K derived for the outer layer,
the number densities of H atoms and H$_2$ molecules are $5.0\times10^{9}$
and $1.6\times10^{10}$~\mbox{cm$^{-3}$}\ (1500~K) and $3.8\times10^{10}$ and
$4.2\times10^{7}$~\mbox{cm$^{-3}$}\ (2100K), respectively.  This leads to
$N$ (H + H$_2$) = (2--4)$\times 10^{10}$~\mbox{cm$^{-3}$}.  With the above $\sigma_{\rm ul}$
and $\varv_{\rm rel}$, we obtain $C_{\rm ul} = 10$~s$^{-1}$ for the outer CO
layer.
These collisional de-excitation rates are much
larger than radiative de-excitation rates $A_{\rm ul}$ of 0.6--1~s$^{-1}$
found for the CO lines analyzed in the present work, which means the
validity of LTE for our modeling.
Therefore, it is unlikely that the high temperatures derived for the
CO layers are just a result of non-LTE effects.

The temperature inversion implies the operation of some heating mechanism
in the outer atmosphere within $\sim$3~\mbox{$R_{\star}$}.
While the outwardly propagating shocks generated by the stellar pulsation
can produce temperature jumps in Mira stars (e.g., Richter et al.
\cite{richter03}), it is not clear whether this
is the case for normal M giants, where the variability amplitudes are
much smaller.  Despite the remarkable difference in the variability
amplitude, BK~Vir shows the temperature inversion in the molecular
component of the outer atmosphere.
This implies that the stellar pulsation may not be the cause of the heating.

Some kind of heating is also required to explain the chromosphere common
among M giants,
although no UV or H$\alpha$ observations of BK~Vir are available in the
literature.
However,
the (electron) temperature of the chromosphere inferred from the UV emission
lines in M giants
is much higher ($\sim$6000---10000~K, Eaton \& Johnson \cite{eaton88};
Luttermoser et al. \cite{luttermoser94})
than the 1900--2100~K derived for the inner CO layer.
Therefore, although the inner CO layer is warmer than the uppermost layer of
the photosphere, the CO gas in the extended outer atmosphere represents a
distinct component other than the chromosphere.

Still, the process responsible for the chromospheric heating may lead to the
formation of both of the hot plasma and warm molecular gas in the outer
atmosphere.
For example, the magnetohydrodynamical (MHD) simulation of stellar winds
in red giants by Suzuki (\cite{suzuki07}) shows the formation of transient
hot gas bubbles embedded in cool gas outflows,
although the simulation is still limited
to stars with relatively high effective temperatures ($\ga$3900~K) and
much less luminous stars ($\la$1000~\mbox{$L_{\sun}$}) compared to BK~Vir.
However, as
Airapetian et al. (\cite{airapetian10}) point out,  this simulation
assumes
fully-ionized plasma, although the gas around K--M giants is only weakly
ionized.  The MHD simulation of Airapetian et al. (\cite{airapetian10})
reproduces the observed terminal wind velocities and mass-loss rates
of K giants, but the agreement between the modeled and observed radial
velocity fields is not yet satisfactory (comparison between the model of
Airapetian et al. \cite{airapetian10} and observed data summarized in
Crowley et al. \cite{crowley09} is shown in Harper \cite{harper11}).
Since the simulation of Airapetian et al. (\cite{airapetian10})
assumes a nearly iso-thermal chromosphere, it
does not include the cool, molecular component.
The extension of these MHD simulations to cooler and more luminous
stars including the modeling of thermal structures
would be useful for understanding the origin of the MOLsphere
in normal red giants.

The presence of the dense CO layers above the photosphere suggests that there
can also be other molecular species in the MOLsphere.  For example, TiO is one
of such molecules, and the contribution from the MOLsphere can significantly
affect the strength of the TiO bands observed in the optical.
Hron et al. (\cite{hron10}) show that the MOLsphere models for the red
supergiant Betelgeuse available in the
literature predict the TiO bands to be too
strong compared to the observed ones.  This is because of the strong
contribution from the TiO molecules in the MOLsphere.
As possible reasons, they suggest the clumpy or patchy nature of the MOLsphere
with a small filling factor and/or the crude nature of the current MOLsphere
models.  In addition, we suggest that the TiO bands may form by scattering
in the MOLsphere.  The line formation by scattering for electronic transitions
(such as the TiO bands) is suggested by Hinkle \& Lambert (\cite{hinkle75}).
The construction of the MOLsphere model with this process taken into account
is beyond the scope of this paper, but should be pursued to obtain a
more comprehensive picture of the MOLsphere.

\section{Concluding remarks}
\label{sect_concl}

We have spatially resolved the normal M7 giant BK~Vir in the individual
CO first overtone lines with VLTI/AMBER.
The uniform-disk diameter shows clear increases by 12--31\% in the
CO lines compared to the continuum.  We detected non-zero/non-$\pi$
CPs and non-zero DPs in the CO lines, which reveal an asymmetry in
the upper photosphere and outer atmosphere where the CO lines form.
The visibilities, CPs, and DPs observed in the individual CO lines are
symmetric with respect to the line center.  This is in marked contrast
with the red supergiant Betelgeuse, in which the vigorous inhomogeneous
gas motions manifest themselves as the asymmetry in the visibilities
in the blue and red wing of the lines.  The absence of such asymmetry
indicates that the amplitude of the inhomogeneous velocity field in
BK~Vir is much smaller ($\la$5~\mbox{km s$^{-1}$}) than in Betelgeuse.

While the MARCS photospheric model can well reproduce the observed CO line
spectrum of BK~Vir, the angular size in the CO lines
predicted by the model is too small.
This indicates the presence of more extended
CO layers than predicted by the photospheric model.  Our model with two
CO layers added above the MARCS model can explain the observed
spectrum, visibilities, and CPs reasonably well.  The derived temperatures
of the two extended CO layers, 1900--2100~K and 1500--2100~K,
are higher than or equal to
that of the uppermost layer of the photosphere.  This result suggests the
operation of some heating mechanism in the outer atmosphere within
$\sim$3~\mbox{$R_{\star}$}.

The present work illustrates that AMBER observations with high-spectral
resolution are effective for constraining the physical properties of the
outer atmosphere.  Given that normal red giants with small variability
amplitudes are not yet intensively
studied by IR spectro-interferometry, it is indispensable to carry out a
systematic survey of a sample of these stars with ranges of
temperatures and luminosities.  This will shed new light on the mass-loss
mechanism not only in normal red giants but also in Mira stars.

\begin{acknowledgement}
We thank the ESO VLTI team for supporting our AMBER observations.
NSO/Kitt Peak FTS data on the Earth's telluric features
were produced by NSF/NOAO.
This publication makes use of data products from the Two Micron All Sky
Survey, which is a joint project of the University of Massachusetts and the
Infrared Processing and Analysis Center/California Institute of Technology,
funded by the National Aeronautics and Space Administration and the National
Science Foundation.
\end{acknowledgement}

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