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264 — 11 December 2014 Editor: Bo Reipurth ([email protected]) List of Contents

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264 — 11 December 2014 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. 264 — 11 December 2014 Editor: Bo Reipurth ([email protected]) List of Contents The Star Formation Newsletter Interview ...................................... 3 My Favorite Object ............................ 6 Editor: Bo Reipurth [email protected] Perspective ................................... 11 Technical Editor: Eli Bressert Abstracts of Newly Accepted Papers .......... 17 [email protected] Abstracts of Newly Accepted Major Reviews . 51 Technical Assistant: Hsi-Wei Yen Dissertation Abstracts ........................ 52 [email protected] New Jobs ..................................... 54 Editorial Board Meetings ..................................... 57 New and Upcoming Meetings ................. 59 Joao Alves Alan Boss Jerome Bouvier Lee Hartmann Thomas Henning Cover Picture Paul Ho Jes Jorgensen NGC 1333 is located at a distance of 235±18 pc Charles J. Lada (determined to the source SVS 13, Hirota et al. Thijs Kouwenhoven PASJ 60, 37, 2008) and most of the cluster mem- Michael R. Meyer bers have an age less than ∼3 Myr, but with a large Ralph Pudritz spread from newly born Class 0 sources to stars Luis Felipe Rodr´ıguez around 10 Myr old. Numerous Herbig-Haro flows Ewine van Dishoeck criss-cross the central cloud core. Hans Zinnecker The image is composed of data from Subaru, DSS, The Star Formation Newsletter is a vehicle for NOAO, and color images by Robert Gendler. fast distribution of information of interest for as- Image assembly and processing by Robert Gendler tronomers working on star and planet formation and Roberto Colombari. and molecular clouds. You can submit material http://www.robgendlerastropics.com for the following sections: Abstracts of recently http://www.astrobin.com/users/rob77/ accepted papers (only for papers sent to refereed journals), Abstracts of recently accepted major re- views (not standard conference contributions), Dis- sertation Abstracts (presenting abstracts of new Ph.D dissertations), Meetings (announcing meet- ings broadly of interest to the star and planet for- Submitting your abstracts mation and early solar system community), New Jobs (advertising jobs specifically aimed towards Latex macros for submitting abstracts persons within the areas of the Newsletter), and and dissertation abstracts (by e-mail to Short Announcements (where you can inform or re- [email protected]) are appended to quest information from the community). Addition- each Call for Abstracts. You can also ally, the Newsletter brings short overview articles submit via the Newsletter web inter- on objects of special interest, physical processes or face at http://www2.ifa.hawaii.edu/star- theoretical results, the early solar system, as well formation/index.cfm as occasional interviews. Newsletter Archive www.ifa.hawaii.edu/users/reipurth/newsletter.htm 2 about the interstellar medium and then to start publishing papers on cloud models in 1973. Bill and I were helped Al Glassgold by a visit with the Townes group at UC Berkeley in the in conversation with Bo Reipurth summer of 1972. Q: Has your physics background been an advantage for your work? A: My physics background has indeed been a primary driver of my research in astrophysics. Many of my pa- pers have been devoted to the clarification and calcula- tion of physical processes, or to providing the microscopic background for complex astrophysical models. A good ex- ample of the latter are the more than a dozen papers with Frank Shu and his collaborators, especially his students Joan Najita, Susana Lizano and Sienny Shang with whom I continue to be close. In the papers dealing with the meteoritic implications of the X-wind model, my nuclear physics background proved helpful. Q: You started out writing a series of papers in the sev- Q: You came to astronomy from a background in physics. enties with Bill Langer. An especially noteworthy paper What motivated that move? from 1974 discussed models of diffuse clouds. What were A: The move actually took years and was stimulated by the main results? several interactions with various colleagues. My early re- A: This paper was the first PDR (photo dissociation re- search in theoretical physics dealt with nuclear scattering, gion) model. The observational motivation for us was the and later I branched out into atomic scattering and ap- early Copernicus UV absorption line studies of interstellar plications of the new many-body techniques to nuclear, diffuse clouds, especially the thicker ones with significant atomic and low temperature physics. Early on this led to amounts of molecular hydrogen. Many others joined in several quantitative treatments of spin-exchange scatter- developing this subject, and the scope of the model was ing between hydrogen atoms, important for understanding immensely extended by the 1985 papers by Tielens and astronomical 21cm radiation. A work more focused on as- Hollenbach. The detailed application of the model to dif- trophysics was a paper entitled ’Anisotropic Superfluidity fuse clouds was greatly advanced by my student, Steven in Neutron Star Matter’, published in the 1970 Physical Federman, and his collaborators. In addition to modeling Review Letters with my student Mark Hoffberg and NYU the clouds, Steve has been active in observing them, and faculty colleagues, Bob Richardson and Mal Ruderman. In he also carried out theoretical and experimental studies of 1964, the Russian theorists Ginzburg and Kirzhnitz had the underlying atomic and molecular physics. suggested that neutron stars are superfluid, and Ruder- Q: Have laboratory studies been helpful in your work on man asked whether this idea could be pursued further. interstellar clouds? I responded positively on the basis of the recent theory of the superfluidity of liquid He-3 based on the Bardeen, A: The discovery of extraterrestrial molecules was a chal- Cooper and Schrieffer (BCS) theory of superconductivity. lenge to both observers and theorists simply because their Unlike the spin-zero electron pairs relevant for supercon- spectra and physical properties were often poorly known, ductivity, the special properties of the nuclear forces led to if at all. As our studies of interstellar and circumstellar 3 P2 neutron pairs as the basis of anisotropic superfluidity matter become progressively more detailed, the results of of neutron star matter. This was Mark Hoffberg’s Ph.D. laboratory studies are still needed. Hardly a day goes by thesis, and it represented the first quantitative treatment without my searching, often unsuccessfully, for some as- of superfluidity in neutron stars. pect of molecular astrophysics. For example, modeling dense molecular regions requires information, now often At this point I was in regular contact with Patrick Thad- lacking, on the excitation of the products of chemical re- deus who was becoming active in the new field of sub-mm actions and of dissociative recombination. The needed radio astronomy. I had met him some ten years earlier laboratory studies are carried out by both chemists and when he was still a graduate student in Charlie Townes physicists, and the experiments are demanding and costly. lab at Columbia University which I visited in connection Sufficient and durable support is needed for young scien- with my interest in new techniques for atomic physics. An tists to develop careers in this area. I fear that this support equally important interaction occurred with the arrival of is now not strong enough. Bill Langer at NYU in 1971. Together we began to learn 3 Q: In 1991 you and your collaborators explored the for- atively short timescales in the inner few AU of the disks mation of molecules in protostellar winds. Do models and around T Tauri stars. This prediction is consistent with observations agree? detections of warm and hot water in these disks obtained A: The 1991 paper with Huggins and Mamon argued that with Spitzer and other instrumentation. It does not rule SiO and other molecules were synthesized in the nascent, out other processes, such as vertical and radial mixing of inner outflows of young protostars. In the ensuing decades water and water ice, but it does indicate that the inner extensive observations of SiO and some other species have regions of protoplanetary disks are able to rapidly process been made of bipolar outflows with mm arrays such as gas phase oxygen into water. The existence of substantial Plateau de Bure, CARMA and SMA. But a resolution of water vapor in the inner few AU of these disks depends a fraction of an arcsecond isn’t enough to get to the heart on the details of the chemistry, which in the case of OH of the matter, i.e., the origin of the jet that drives the and water is sensitive to the gas temperature and to the outflows. Future observations with ALMA at the highest formation of molecular hydrogen. resolution may finally do the job. Of course the models Q: In one of your most recent papers you have re-visited of the outflows need to be improved in light of significant cosmic-ray and X-ray heating of clouds and disks. What advances is astrochemistry over the intervening years. Si- are the new physical ingredients in these calculations? enny Shang at ASIAA is pursuing this line of research and A: The main new direction is a more complete analysis also encouraging the appropriate observations. of the chemical reactions induced by the primary prod- + + Q: Did the discovery of extreme overabundances of for ex- ucts of X-rays ionization, the H2 and H3 ions. We have ample SiO and CH3OH in the L1157 outflow and some recently extended this idea to FUV photodissociation in other flows come as a surprise? molecular regions. The heating from the absorption of A: More delight than surprise! FUV radiation by neutral species in dense molecular gas is dominated by the energy yield from the chemical reactions Q: Your well cited paper from 1997 deals with X-ray ion- induced by the products of photodissociation or photoion- ization of protoplanetary disks, a study you followed up in ization.
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