ALMA2019: Science Results and Cross-Facility Synergies

Session

ISM, SF

III

14 Oct 2019, 15:00

T-Hotel Cagliari

Description

Chair of the session:

24. ALMA-IMF Large program, toward the understanding of the origin of the IMF

Dr Fabien Louvet

14/10/2019, 15:00

Invited talk

Abstract:
"Understanding the processes that determine the stellar Initial Mass Function (IMF) is a critical unsolved problem, with profound implications for many areas of astrophysics (Offner et al. 2014). In molecular clouds, stars are formed in cores, gas condensations which are sufficiently dense so that gravitational collapse converts most of their mass into a star or a small...

26. Probing with ALMA the evolution of cores on the cusp of star formation

Dr Rachel Friesen

14/10/2019, 15:25

Contributed talk

Abstract:
"While clearly a vital step in the process of star formation, the transition from prestellar core to first hydrostatic core (FHSC) or protostar has not been well studied observationally. Even with ALMA, dense condensations within starless cores are very rarely detected in large surveys. Here, we present Atacama Large Millimeter/submillimeter Array (ALMA)...

27. ALMA observations of extremely young star-forming cores

Dr Maria Jose Maureira

14/10/2019, 15:40

Contributed Talk

29. Converging filaments and the formation of a super star cluster in SgrB2

Dr Alvaro Sanchez-Monge

14/10/2019, 15:55

Contributed talk

Abstract:
"The star formation process is intimately related to the existence of disks, which mediate the accretion onto the star, and energetic outflows, which help to remove angular momentum from the system. Over the last years, this paradigm has been widely favoured for stars of all masses: from low-mass through B-type stars up to the most massive O-type stars. However, for...

33. Star formation and magnetic fields in the ALMA era

Dr Chat Hull

15/10/2019, 09:00

Invited talk

Abstract:
"New ALMA polarization observations continue to both expand and confound our understanding of the role played by the magnetic field in low-mass star formation.  The sample of very young, Class 0 protostellar sources observed with high resolution and high sensitivity with ALMA is now large enough that we are beginning to see the same surprising features in multiple...

34. Dissipation Scale of Turbulence Cascade Revealed by ALMA

Dr Jin Koda

15/10/2019, 09:25

Contributed talk

36. ALMA Detection of a Linearly Polarised Reverse Shock in GRB 190114C

Dr Tanmoy Laskar

15/10/2019, 09:40

Contributed talk

Abstract:
"We present the earliest observation and first detection of polarized millimeter emission in a γ-ray burst with ALMA Cycle 7 Band 3 (97.5 GHz) observations of GRB 190114C. With observations spanning 2.2 to 5.2 hours after the burst, we detect linear polarization in the GRB afterglow at ~ 5σ, decreasing from Π=(0.87±0.13)% to (0.60±0.19)%, and evolving in...

37. ALMA reveals a magnetically-regulated scenario for protostellar collapse: B335 & future perspectives.

Dr Anaëlle Maury

15/10/2019, 09:55

Contributed talk

Abstract:
"Understanding the first steps in the formation of stars and protoplanetary disks is a great unsolved problem of modern astrophysics. Observationally, the key to constraining theoretical models lies in high-resolution studies of the youngest protostars. I will show our SMA and ALMA observations of the magnetic field topology in a sample of young protostars, and...

38. Tracing B-fields in protostellar targets across spatial scales with ALMA, SOFIA, BLAST, and APEX.

Dr Giles Novak

15/10/2019, 10:10

Contributed talk

Abstract:
"To understand the formation of stars and protoplanetarydisks in magnetized molecular clouds we require both (a) polarization maps of B-fields in protostellar infall envelopes, from ALMA, and (b) larger-scale B-field maps that serve to reveal the linkages - if any - between these envelope fields and the fields of the parent clouds.  We will present new results from...

49. Early High-Mass Star Formation: A Comprehensive ALMA ATLAS

Dr Thushara Pillai

15/10/2019, 17:10

Invited talk

Abstract:
I will present the results from our survey of Cold Cores with ALMA (CoCoA). Star formation research has still not revealed the initial conditions for high-mass star formation (HMSF). This is largely due to the lack of clear-cut examples of dense clumps that are bound to form stars but have not done so yet (high--mass starless clumps: HMSCs). While scattered, small sky...

50. Sub-arcsecond (sub)millimeter imaging of the massive protostellar outburst in G358.93-0.03

Dr Crystal Brogan

15/10/2019, 17:35

Contributed talk

Abstract:
"The recent identification of accretion outbursts in two massive protostars, both heralded by 6.7 GHz methanol maser flares, has invigorated single-dish maser monitoring programs on a quest to find more cases. As a result, a third event was discovered on 14-Jan-2019 in a poorly-studied massive star-forming region G358.93-0.03. Since then, the global maser community...

52. Dissecting high-mass protostars with SPARKS

Dr Timea Csengeri

15/10/2019, 17:50

Contributed talk

Abstract:
"The origin of the highest mass stars is still an enigma in modern astrophysics. The SPARKS project (Search for high-mass protostars with ALMA up to 5 kpc) is a high angular resolution follow-up of the complete sample of infrared quiet massive clumps selected from the ATLASGAL survey at 870 micron. ALMA confirms that deeply embedded high-mass protostars are already...

53. Exploring the Complex Chemistry of Young Solar Systems

Dr Jes Jørgensen

15/10/2019, 18:05

Contributed talk

Abstract:
Studies of the complex organic chemistry in regions of star and planet formation have taken a tremendous step forward with data from ALMA. With its unprecedented sensitivity and angular resolution, ALMA has made it possible to zoom in on the gas surrounding deeply embedded protostars on Solar System scales. Such observations reveal the details of the rich...

54. From the dense core edge to the disk scales

Dr Jaime Pineda

15/10/2019, 18:20

Contributed talk

Abstract:
"Dense cores are the places where stars are formed within the supersonic Molecular Clouds. These dense regions (n~10^5 cc) are cold (T~10 K) and display subsonic levels of turbulence (Mach ~ 0.5), and represent the initial conditions for both star and disk formation. Therefore, it is crucial to study dense cores to better understand the star and disk formation...

55. The early stages at substellar formation in Lupus 1 and 3 clouds

Dr Alejandro Santamaría-Miranda

15/10/2019, 18:35

Contributed talk

Abstract:
"The formation of brown dwarfs is still under debate. While the latest discoveries point towards a scaled-down version of the star formation process, other models, such as embryo ejection or stellar disk fragmentation, may not be discarded. Here we present our latest ALMA cycle 3 (band 6) continuum observations of Lupus 1 and 3 star formation regions based on...

15. Chemical Diversity and Evolution toward Protoplanetary Disks

Dr Nami Sakai

18/10/2019, 09:00

Invited talk

Abstract:
Star and planet formation is one of the most fundamental structure-formation processes in the Universe. Physical processes of star and planet formation have widely been investigated as one of the major targets of observational astronomy and astrophysics during the last few decades. Meanwhile, star and planet formation is inevitably accompanied with the evolution of...

16. ALMA observations of the DG Tau B Class I protostar disk and CO outflow

Dr Aloïs De Valon

18/10/2019, 09:25

Contributed talk

Abstract:
Powerful atomic jets and molecular outflows are observed in young protostars at all stages of active accretion, from the young embedded Class 0 and Class 1 phases to the later optically revealed T Tauri or Class 2 phase. The origin of the ejection, its role in angular momentum extraction and impact on protoplanetary disk evolution remain as fundamental open...

17. Chronology of Episodic Accretion in Protostars - an ALMA survey of the CO and H2O snow lines

Dr Tien-Hao Hsieh

18/10/2019, 09:40

Contributed talk

Abstract:
Episodic accretion is nowadays a well accepted process in low-mass star formation, but its origin and influence on star forming process are not yet fully understood. We present an ALMA survey of N2H+ (1 − 0) and HCO+ (3 − 2) toward 39 Class 0 and Class I sources in the Perseus molecular cloud. N2H+ and HCO+ are destroyed via gas-phase reactions with CO and H2O,...

18. Probing fragmentation and velocity sub-structure in the massive NGC 6334 filament with ALMA.

Dr Yoshito Shimajiri

18/10/2019, 09:55

Contributed talk

Abstract:
"Herschel imaging surveys of Galactic interstellar clouds support a paradigm for low-mass star formation in which dense molecular filaments play a crucial role. The detailed fragmentation properties of star-forming filaments remain poorly understood, however, and the validity of the filament paradigm in the high-mass regime is still unclear. Here, we investigate...

19. Sounding diffuse molecular gas with ALMA as a mean to prove that the CO-dark gas is molecular

Dr Maryvonne Gerin

18/10/2019, 10:10

Contributed talk

Abstract:
Studies of the dust continuum emission and extinction, and of the gamma ray emission show that a fraction of the interstellar gas is not traced by the combination of HI 21 cm and CO J=1-0 emission lines. The nature and physical conditions of this so called CO-dark gas are debated. We have used ALMA to search for molecular absorption towards distant quasars in the...