Distance to Orion KL Measured with VERA

Hirota, Tomoya; Bushimata, Takeshi; Choi, Yoon Kyung; Honma, Mareki; Imai, Hiroshi; Iwadate, Kenzaburo; Jike, Takaaki; Kameno, Seiji; Kameya, Osamu; Kamohara, Ryuichi; Kan-ya, Yukitoshi; Kawaguchi, Noriyuki; Kijima, Minoru; Kim, Mi Kyoung; Kobayashi, Hideyuki; Kuji, Seisuke; Kurayama, Tomoharu; Manabe, S.; Maruyama, Kenta; Matsui, Makoto; Matsumoto, Naoko; Miyaji, Takeshi; Nagayama, Tomonori; Nakagawa, Akiharu; Nakamura, Kayoko; Oh, Chung Sik; Omodaká, Toshihiro; Oyama, Tomoaki; Sakai, Satoshi; Sasao, Tetsuo; Sato, Katsuhisa; Sato, M.; Shibata, Katsunori M.; Shintani, Motonobu; Tamura, Yoshiaki; Tsushima, Miyuki; Yamashita, K.

doi:10.1093/pasj/59.5.897

Cited by 173 publications

(60 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The larger the aperture, the more envelope emission, but also extended emission from the surrounding filament and emission from neighboring sources is included. We find that, for isolated protostars in the Orion star-forming region (distance of ∼420 pc; Menten et al 2007;Hirota et al 2007), aperture radii of ∼10 in the far-IR (70-160 μm) capture most of the emission from the envelope at these wavelengths (see E. Furlan et al 2014, in preparation). Choosing larger radii risks including surrounding emission that is not associated with the envelope.…”

Section: The Bolometric Luminosity Of the Protostar Omc-2 Firmentioning

confidence: 73%

On the Nature of the Deeply Embedded Protostar Omc-2 Fir 4

Furlan

Megeath

Osorio

et al. 2014

ApJ

View full text Add to dashboard Cite

We use mid-infrared to submillimeter data from the Spitzer, Herschel, and Atacama Pathfinder Experiment telescopes to study the bright submillimeter source OMC-2 FIR 4. We find a point source at 8, 24, and 70 μm, and a compact, but extended source at 160, 350, and 870 μm. The peak of the emission from 8 to 70 μm, attributed to the protostar associated with FIR 4, is displaced relative to the peak of the extended emission; the latter represents the large molecular core the protostar is embedded within. We determine that the protostar has a bolometric luminosity of 37 L , although including more extended emission surrounding the point source raises this value to 86 L . Radiative transfer models of the protostellar system fit the observed spectral energy distribution well and yield a total luminosity of most likely less than 100 L . Our models suggest that the bolometric luminosity of the protostar could be as low as 12-14 L , while the luminosity of the colder (∼20 K) extended core could be around 100 L , with a mass of about 27 M . Our derived luminosities for the protostar OMC-2 FIR 4 are in direct contradiction with previous claims of a total luminosity of 1000 L . Furthermore, we find evidence from far-infrared molecular spectra and 3.6 cm emission that FIR 4 drives an outflow. The final stellar mass the protostar will ultimately achieve is uncertain due to its association with the large reservoir of mass found in the cold core.

show abstract

Section: The Bolometric Luminosity Of the Protostar Omc-2 Firmentioning

confidence: 73%

On the Nature of the Deeply Embedded Protostar Omc-2 Fir 4

Furlan

Megeath

Osorio

et al. 2014

ApJ

View full text Add to dashboard Cite

show abstract

“…For stars on the main sequence, this removes a major source of error that arises in the conversion between absolute magnitude and mass for field stars. Moreover, the stars are all at nearly the same distance, and for at least some clusters this distance is known quite precisely from interferometrybased parallaxes to radio-flare stars (e.g., Hirota et al 2007;Sandstrom et al 2007;Menten et al 2007;Reid et al 2009). Low-mass stars and brown dwarfs are also much brighter when they are young, they are far easier to detect in clusters than in the field.…”

Section: Young Clustermentioning

confidence: 99%

The big problems in star formation: The star formation rate, stellar clustering, and the initial mass function

2014

View full text Add to dashboard Cite

Star formation lies at the center of a web of processes that drive cosmic evolution: generation of radiant energy, synthesis of elements, formation of planets, and development of life. Decades of observations have yielded a variety of empirical rules about how it operates, but at present we have no comprehensive, quantitative theory. In this review I discuss the current state of the field of star formation, focusing on three central questions: what controls the rate at which gas in a galaxy converts to stars? What determines how those stars are clustered, and what fraction of the stellar population ends up in gravitationally-bound structures? What determines the stellar initial mass function, and does it vary with star-forming environment? I use these three question as a lens to introduce the basics of star formation, beginning with a review of the observational phenomenology and the basic physical processes. I then review the status of current theories that attempt to solve each of the three problems, pointing out links between them and opportunities for theoretical and numerical work that crosses the scale between them. I conclude with a discussion of prospects for theoretical progress in the coming years.

show abstract

“…The closest region where this happens is the Orion Nebula Cluster (Hillenbrand, 1997;Hillenbrand & Hartmann, 1998). It lies at a distance of 410 pc (Sandstrom et al, 2007;Menten et al, 2007;Hirota et al, 2007;Caballero, 2008). A rich cluster somewhat further away is associated with the Monoceros R2 cloud (Carpenter et al, 1997) at a distance of ∼ 830 pc.…”

Section: Spatial Distributionmentioning

confidence: 99%

Physical Processes in the Interstellar Medium

Klessen

Glover

2015

Saas-Fee Advanced Course

170

View full text Add to dashboard Cite

Interstellar space is filled with a dilute mixture of charged particles, atoms, molecules and dust grains, called the interstellar medium (ISM). Understanding its physical properties and dynamical behavior is of pivotal importance to many areas of astronomy and astrophysics. Galaxy formation and evolution, the formation of stars, cosmic nucleosynthesis, the origin of large complex, prebiotic molecules and the abundance, structure and growth of dust grains which constitute the fundamental building blocks of planets, all these processes are intimately coupled to the physics of the interstellar medium. However, despite its importance, its structure and evolution is still not fully understood. Observations reveal that the interstellar medium is highly turbulent, consists of different chemical phases, and is characterized by complex structure on all resolvable spatial and temporal scales. Our current numerical and theoretical models describe it as a strongly coupled system that is far from equilibrium and where the different components are intricately linked together by complex feedback loops. Describing the interstellar medium is truly a multi-scale and multi-physics problem. In these lecture notes we introduce the microphysics necessary to better understand the interstellar medium. We review the relations between large-scale and small-scale dynamics, we consider turbulence as one of the key drivers of galactic evolution, and we review the physical processes that lead to the formation of dense molecular clouds and that govern stellar birth in their interior.

show abstract

Distance to Orion KL Measured with VERA

Cited by 173 publications

References 23 publications

On the Nature of the Deeply Embedded Protostar Omc-2 Fir 4

On the Nature of the Deeply Embedded Protostar Omc-2 Fir 4

The big problems in star formation: The star formation rate, stellar clustering, and the initial mass function

Physical Processes in the Interstellar Medium

Contact Info

Product

Resources

About