ﻻ يوجد ملخص باللغة العربية
Using high-resolution (sub-kiloparsec scale) submillimeter data obtained by ALMA, we analyze the star formation rate (SFR), gas content and kinematics in SDP 81, a gravitationally-lensed star-forming galaxy at redshift 3. We estimate the SFR surface density ($Sigma_{mathrm{SFR}}$) in the brightest clump of this galaxy to be $357^{+135}_{-85},mathrm{M_{odot},yr^{-1},kpc^{-2}}$, over an area of $0.07pm0.02,mathrm{kpc}^2$. Using the intensity-weighted velocity of CO$,$(5-4), we measure the turbulent velocity dispersion in the plane-of-the-sky and find $sigma_{mathrm{v,turb}} = 37pm5,mathrm{km,s}^{-1}$ for the star-forming clump, in good agreement with previous estimates along the line of sight. Our measurements of gas surface density, freefall time and turbulent Mach number reveal that the role of turbulence is vital to explaining the observed SFR in this clump. While the Kennicutt Schmidt (KS) relation predicts a SFR surface density of $Sigma_{mathrm{SFR,KS}} = 52pm17,mathrm{M_{odot},yr^{-1},kpc^{-2}}$, the single-freefall model by Krumholz, Dekel and McKee (KDM) predicts $Sigma_{mathrm{SFR,KDM}} = 106pm37,mathrm{M_{odot},yr^{-1},kpc^{-2}}$. In contrast, the multi-freefall (turbulence) model by Salim, Federrath and Kewley (SFK) gives $Sigma_{mathrm{SFR,SFK}} = 491^{+139}_{-194},mathrm{M_{odot},yr^{-1},kpc^{-2}}$. Although the SFK relation overestimates the SFR in this clump (possibly due to the ignorance of magnetic field), it provides the best prediction among the available models. Finally, we compare the star formation and gas properties of this high-redshift galaxy to local star-forming regions and find that the SFK relation provides the best estimates of SFR in both local and high-redshift galaxies.
We probe the star formation properties of the gas in AzTEC-1 in the COSMOS field, one of the best resolved and brightest starburst galaxies at $z approx 4.3$, forming stars at a rate > 1000 $mathrm{M_{odot}},mathrm{yr^{-1}}$. Using recent ALMA observ
Analyses of high-redshift ultraluminous infrared (IR) galaxies traditionally use the observed optical to submillimeter spectral energy distribution (SED) and estimates of the dynamical mass as observational constraints to derive the star formation ra
We present high-resolution observations of the 880 $mu$m (rest-frame FIR) continuum emission in the z$=$4.05 submillimeter galaxy GN20 from the IRAM Plateau de Bure Interferometer (PdBI). These data resolve the obscured star formation in this unlense
I present a model for the star formation properties of z~2 starburst galaxies. Here, I discuss models for the formation of high-z Submillimeter Galaxies, as well as the CO-H2 conversion factor for these systems. I then apply these models to literatur
We combine data from ALMA and MUSE to study the resolved (~300 pc scale) star formation relation (star formation rate vs. molecular gas surface density) in cluster galaxies. Our sample consists of 9 Fornax cluster galaxies, including spirals, ellipti