254 — 13 February 2014 Editor: Bo Reipurth ([email protected]) List of Contents
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THE STAR FORMATION NEWSLETTER An electronic publication dedicated to early stellar/planetary evolution and molecular clouds No. 254 — 13 February 2014 Editor: Bo Reipurth ([email protected]) List of Contents The Star Formation Newsletter Interview ...................................... 3 My Favorite Object ............................ 5 Editor: Bo Reipurth [email protected] Perspective ................................... 10 Technical Editor: Eli Bressert Abstracts of Newly Accepted Papers .......... 13 [email protected] Abstracts of Newly Accepted Major Reviews . 54 Technical Assistant: Hsi-Wei Yen Dissertation Abstracts ........................ 60 [email protected] New Jobs ..................................... 61 Editorial Board Meetings ..................................... 63 Summary of Upcoming Meetings ............. 66 Joao Alves Alan Boss Short Announcements ........................ 67 Jerome Bouvier New Books ................................... 68 Lee Hartmann Thomas Henning Paul Ho Jes Jorgensen Charles J. Lada Cover Picture Thijs Kouwenhoven Michael R. Meyer This image shows the blueshifted outflow cav- Ralph Pudritz ity from the embedded quadruple Class I source Luis Felipe Rodr´ıguez L1551 IRS5 based on Hα and [SII] images obtained Ewine van Dishoeck with the Subaru telescope images. Two short jets, Hans Zinnecker HH 154, are seen to emerge from the source region to the upper left. The outflow cavity has burst The Star Formation Newsletter is a vehicle for through the front of the cloud, exposing the rich fast distribution of information of interest for as- and complex Herbig-Haro shock structures within. tronomers working on star and planet formation A few faint knots from the HH 30 jet (outside the and molecular clouds. You can submit material field) are visible at the top of the image. The for the following sections: Abstracts of recently field is about 7×8 arcmin, corresponding to about accepted papers (only for papers sent to refereed 0.30×0.35 pc at the assumed distance of 150 pc. journals), Abstracts of recently accepted major re- North is up and east is left. views (not standard conference contributions), Dis- sertation Abstracts (presenting abstracts of new Subaru images: Bo Reipurth Ph.D dissertations), Meetings (announcing meet- Color-composite: Robert Gendler ings broadly of interest to the star and planet for- (http://www.robgendlerastropics.com). mation and early solar system community), New Jobs (advertising jobs specifically aimed towards persons within the areas of the Newsletter), and Short Announcements (where you can inform or re- quest information from the community). Addition- Submitting your abstracts ally, the Newsletter brings short overview articles on objects of special interest, physical processes or Latex macros for submitting abstracts theoretical results, the early solar system, as well and dissertation abstracts (by e-mail to as occasional interviews. [email protected]) are appended to each Call for Abstracts. You can also submit via the Newsletter Archive Newsletter web interface at http://www2.ifa. www.ifa.hawaii.edu/users/reipurth/newsletter.htm hawaii.edu/star-formation/index.cfm 2 in ISM and star formation. Universities wise, besides PKU and its Kavli institute, Nanjing U., Tsinghua U., Beijing Yuefang Wu Normal U., Guangzhou U., Hebei Normal U., Xiangtan in conversation with Bo Reipurth U., Tibet U. have research groups of this field. Very re- cently, Yunnan U. has created and filled leading scholar position of this field. Workshops, conferences, training classes in star formation are held frequently. In 2007, our group held the ”Cross-Straits Workshop on Star Forma- tion” at PKU. Experts gave lectures to nearly 50 young as- tronomers. We also held the ”ISM 2010” meeting with the subject ”The Frontier on Interstellar Medium - 40th An- niversary of the Discovery of CO in ISM” at KIAA/PKU, which had attracted more than one hundred experts and young astronomers world wide. Q: A very influential paper of yours dealt with high veloc- ity molecular outflows from both low-mass and high-mass young stars. What were your main conclusions, and do you still work in this area? Q: You have been engaged in studies of star forming re- A: The outflow mass was found to correlate strongly with gions for many years. When did you develop this interest? bolometric luminosity of the center source. There are also A: I entered the Astronomy Division at Peking U. (PKU) correlations among the central source luminosity and the about 10 years after I graduated from a 6-year university parameters of mechanical luminosity and the force nec- program in 1964. My original major was nuclear physics, essary to drive the outflow. These results suggest that which was interrupted by two years practical work in the the luminosity of the central stellar source determines the ”Four-Clear-Ups” in the countryside for new faculty. Be- mass, momentum and energy of the outflows. Although fore the end of this practice the Cultural Revolution began the radiation pressure of the central sources is not enough and lasted till the early 70’s. These activities took a lot of to drive the outflows, the driving mechanism should be time away from my science career but gave me a chance stellar but non-radiative. This is a key to understand the to contemplate my academic interests. In the 70’s the physical processes of star formation, because the outflow- education/research system had gradually recovered. Sev- driving mechanism is an essential distinction in the prin- eral colleagues and I began some research in interstellar cipal models of massive star formation. We also found molecules and the ISM. Inspired by the series of papers that these correlations exist in a wide range of bolometric −1 6 on molecular cloud energetics by Evans et al. we began to luminosity from 10 to 10 L⊙, indicating similarities in examine the heating and cooling mechanisms of interstel- the driving mechanism between low- and high-mass out- lar gas and dust. Our first target was W40 (S64). At that flows. It suggests that high-mass stars form in a similar time we just used the published CO and infrared data by way as low-mass stars. However, there are also differences Zeilik & Lada. Later on we studied this interesting object between high- and low-mass outflows. For example, high- in lines of CO (1-0) (3-2) and 13CO (2-1) (3-2). A weak mass outflows are generally less collimated than low-mass outflow and the discrepancy of the core peak and the Hii outflows. This difference may be due to the environment region were revealed. Last year, Pirogov et al. found evi- and evolutionary states of the central sources. We are still dence of interaction between the ionized and neutral ma- continuing with this investigation of outflows. We have ex- terials and possible triggers of star formation around this tended our study of massive star feed back to the phases ii source. And Mallick et al. revealed an embedded cluster later than UC H regions. at the Herschel filament junction. A comparison of earlier Q: So outflows offer evidence to support the accretion model and new results of this source witnesses the development for high-mass star formation. How about inflow? Is this of star formation studies during the recent three decades. also similar in the formation of low- and high- mass stars? Q: You were one of the pioneers in opening up the subject of star formation in China. What is the status today? A: Yes, inflow is also critical to distinguish models of A: In the early 80’s there were only few groups and about a spherical infall, disk accretion and mergers by less massive dozen researchers working on star formation. Now Purple stellar objects. Since 2003 several surveys of inflow mo- Mountain Observatory (PMO), National Astronomical ob- tion in high-mass star forming regions have been carried servatories, Shanghai Observatory, Yunnan Observatory, out. We made a mapping survey of two group samples and Xinjiang Observatory all have science teams working with different evolution phases, one group consisting of 3 UCHii regions and the other UCHii precursors (UCHiiP), telescopes are being built in our country. Besides the al- younger than the former. Seventeen sources were detected ready constructed 65m in Shanghai, projects of the Dome with inflow signatures, known as ”blue profile”. The ex- A Terahertz Explorer-5 (DATE5) and 110m radio tele- cess of blue over red profiles is 17% for the UCHiiP and scope in Qitai (QTT) are in progress. The Five-Hundred- 58% for UCHii, suggesting that the inflows are occurring Meter Aperture Spherical Radio Telescope (FAST) at Da- more frequently in regions with stronger radiation. This wodang is expected to see first light in two years. China is consistent with the disk-accretion model and does not also joined Herschel and SKA. Besides, our country has favor the other two models. Another difference is that the also begun to help in operating telescopes and sharing the blue excess in the low-mass sources does not clearly show time. Such collaboration for medium and large optical- such an evolutionary trend. The reasons need to be ex- infrared telescopes was begun in 2011. And a similar plored but in general, it shows that the infall motion is still project for sub-millimeter telescopes is in discussion now. ongoing during the UCHii phase. To test these single-dish I believe that these new facilities and projects will help us results we investigated infall candidates in high-mass cores to build a bright academic future. Domestic and interna- using high resolution data. So far UCHii regions G19.61- tional co-operations will be further developed. 0.23, G9.62+0.19E, NGC7538 IRS1, G10.6-0.4, G34.26- Q: Most recently, you have been engaged in studies of ii 0.15 and UCH P cores JCMT18354, W3-SE, G9.62+0.19F, Planck cold dust clumps.