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333 — 15 September 2020 Editor: Bo Reipurth (Reipurth@Ifa.Hawaii.Edu) List of Contents THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar/planetary evolution and molecular clouds No. 333 — 15 September 2020 Editor: Bo Reipurth ([email protected]) List of Contents The Star Formation Newsletter Editorial ....................................... 3 Interview ...................................... 4 Editor: Bo Reipurth [email protected] My Favorite Object ............................ 7 Associate Editor: Anna McLeod Perspective ................................... 14 [email protected] Abstracts of Newly Accepted Papers .......... 18 Technical Editor: Hsi-Wei Yen Abstracts of Newly Accepted Major Reviews .. 51 [email protected] Dissertation Abstracts ........................ 52 Editorial Board New Jobs ..................................... 56 Short Announcements ........................ 58 Joao Alves Alan Boss Meetings ..................................... 59 Jerome Bouvier Summary of Upcoming Meetings .............. 60 Lee Hartmann Thomas Henning New Books ................................... 61 Paul Ho Passings ...................................... 63 Jes Jorgensen Charles J. Lada Thijs Kouwenhoven Michael R. Meyer Ralph Pudritz Luis Felipe Rodríguez Cover Picture Ewine van Dishoeck Hans Zinnecker The image shows the active star forming regions of M8 and M20 and associated giant molecular clouds, The Star Formation Newsletter is a vehicle for together with the hidden Galactic Center to the fast distribution of information of interest for as- lower left. The small Bok globule Barnard 86 is tronomers working on star and planet formation seen near the center of the image against the rich and molecular clouds. You can submit material star fields of Sagittarius. The vertical axis is 10◦, for the following sections: Abstracts of recently with north up and east left. accepted papers (only for papers sent to refereed journals), Abstracts of recently accepted major re- Image by Bo Reipurth (Canon EOS Ra, 30 sec, views (not standard conference contributions), Dis- 135mm lens at f/2, ISO 6400). sertation Abstracts (presenting abstracts of new Ph.D dissertations), Meetings (announcing meet- ings broadly of interest to the star and planet for- mation and early solar system community), New Jobs (advertising jobs specifically aimed towards persons within the areas of the Newsletter), and Submitting your abstracts Short Announcements (where you can inform or re- quest information from the community). Addition- Latex macros for submitting abstracts ally, the Newsletter brings short overview articles and dissertation abstracts (by e-mail to on objects of special interest, physical processes or [email protected]) are appended to theoretical results, the early solar system, as well each Call for Abstracts. You can also as occasional interviews. submit via the Newsletter web inter- face at http://www2.ifa.hawaii.edu/star- Newsletter Archive formation/index.cfm www.ifa.hawaii.edu/users/reipurth/newsletter.htm Editorial After 28 years and 333 issues of the Star Formation Newsletter, I have decided that the time has come for me to step down as Editor of the Newsletter. While it has been wonderful to interact with our community and I am thankful for the many expressions of appreciation I have received over the years, it has also been a challenge every month to find the time to prepare an issue, no matter what other things I was doing, or where I was. Technology inexorably advances, and new means of communication appear. 28 years ago the world looked very different, as we were only at the beginning of the information age, and it may be difficult for young people today to understand that information was not so easy to get hold of as it is now. Back then many institutes still issued preprints and mailed them to other institutes. The process of publishing a paper was much slower, and people actually went to the library and (gasp) read the journals as they came in. It was in that environment that the Star Formation Newsletter was launched as the first electronic newsletter in astronomy, offering rapid dissemination not only of abstracts, but also of news about meetings, jobs, dissertations, and new books. This soon led to more such newsletters being circulated in other fields of astronomy, most of which unfortunately had short lives, although some still exist. About 8 years ago I expanded the Newsletter to also include interviews with leading researchers, and short articles meant to give quick overviews about particular subjects or specially interesting objects. Although I step down as Editor, it does not mean that the Newsletter ceases to exist. I am very happy to announce that João Alves at the University of Vienna, Austria, has agreed to take the helm. Joao will gradually introduce changes to the Newsletter, and in next month’s issue he will lay out his vision. I will continue to prepare interviews for the Newsletter, since they have been universally welcomed by readers. I have come to realize that, subsequent to publication, the interviews have been buried in the archives on the webpage for the Newsletter, and while still accessible it is a major effort to find any specific one. Hence, I have decided to make a compilation of all 77 interviews so far,. This facilitates finding particular ones, but - perhaps more importantly - allows young researchers to see more globally how star formation has developed into its present state. The compilation, which will be augmented yearly, is further described in the section on New Books in this issue, and it can be downloaded from this URL: http://bit.ly/77interviews It has always been a puzzle to me that I only receive about 50% of the abstracts of relevant papers. Given that we all publish to be read, it seems logical that, after spending many months to prepare research results for publication, one should also spend 5 minutes to circulate an abstract to potential readers. I therefore urge readers to submit their abstracts to João in the spirit of a shared community. If we all do this, we all can benefit from a near-complete monthly compilation. The Newsletter is a creation of the star formation community for the star formation community. So please support João in his future efforts on behalf of our community. In closing, I would like to thank all the readers who have submitted their abstracts and announcements to the Newsletter. I would like to extend special thanks to my Associate Editors Hsi-Wei Yen and Anna McLeod who have been steadfast in their support of the Newsletter. Finally, on a practical note, please continue to submit your abstracts to the Newsletter website at its current location until further notice. Bo Reipurth 3 replace George Coyne on my Ph.D. Committee as Charlie was transitioning to become an Assistant Professor at Uni- Bruce Wilking versity of Arizona (Coyne had left to become the Director in conversation with Bo Reipurth of the Vatican Observatory). Q: Your PhD from 1981 focused on star formation in the ρ Ophiuchi cloud. How did you choose that subject? A: I was fortunate that Charlie Lada arrived at the Uni- versity of Arizona as a Bok Fellow in 1978. He wanted to do infrared surveys of molecular clouds and I assisted him with infrared observations of Barnard 35 at the Mt. Lem- mon 28-inch telescope. In return, he offered to take me observing at the Millimeter Wave Observatory (MWO) in West Texas. We had done some near-infrared polariza- tion measurements of stars toward the ρ Oph cloud and I thought I was seeing two cloud components. So I began observing 12C16O emission in the direction of these stars and found the line profiles to be very complex and very optically thick. So Charlie suggested tuning to 13C16O, Q: While you were still a student you led a study on the but we found these too looked optically thick. So right 12 18 wavelength dependence of interstellar linear polarization. before we were to return to Tucson, we tuned to C O This has remained a highly cited paper for 40 years, what and found a single strong emission line. On subsequent 12 18 accounts for this longevity? trips we started mapping the cloud in C O only to find that the resident astronomer, Bob Loren, was already do- A: As near-infrared polarization data of stars were becom- ing so. When Bob found out I was hoping to make this ing more available, a more versatile functional form for part of my dissertation, he graciously stepped aside and the wavelength dependence of polarization was needed. gave me the project. George and Marcia Rieke had already measured a large 12 18 sample of field stars with one of the first near-infrared po- Once we had done a higher resolution C O map of the larimeters, built by James Kemp, and I joined the effort. L1688 cloud with the NRAO 12-meter telescope, I carried With the help of Peter Martin, who was visiting the Uni- out a near-infrared survey of the highest column density versity of Arizona at the time, we added an additional region using George and Marcia’s InSb detector at the 61- free parameter to the lognormal Serkowski Law and pro- inch telescope on Mt. Bigelow. This multi-wavelength posed some physical significance to this addition. Kristof approach to studying star formation was relatively new. I Serkowski was also at the University of Arizona and was surveyed a 10’ x 10’ region by raster scanning with a single supportive of us tinkering with his “Law". The relation- detector across the region over 4 nights. ship we proposed in 1980, and in a follow-up study of Back when I was a student, observational astronomy was sources with more extreme values of λmax, was confirmed very hands-on. There were no telescope operators at MWO by subsequent studies and became a standard marker for or Mt. Bigelow. At MWO, you had to tune the klystron interstellar dust in the Galaxy.
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