What drives the [CII]/FIR deficit in submillimeter galaxies?

Large scale structure and cosmolog

Constraining the Volume Density of Dusty Star-forming Galaxies through the First 3 mm Number Counts from ALMA

Large scale structure and cosmolog

Invariant tensors for simple groups

The forms of the invariant primitive tensors for the simple Lie algebras A_l, B_l, C_l and D_l are investigated. A new family of symmetric invariant tensors is introduced using the non-trivial cocycles for the Lie algebra cohomology. For the A_l algebra it is explicitly shown that the generic forms of these tensors become zero except for the l primitive ones and that they give rise to the l primitive Casimir operators. Some recurrence and duality relations are given for the Lie algebra cocycles. Tables for the 3- and 5-cocycles for su(3) and su(4) are also provided. Finally, new relations involving the d and f su(n) tensors are given.Comment: Latex file. 34 pages. (Trivial) misprints corrected. To appear in Nucl. Phys.

Probing star formation and ISM properties using galaxy disk inclination: III. Evolution in dust opacity and clumpiness between redshift 0.0 < z < 0.7 constrained from UV to NIR

Interstellar matter and star formatio

An ultra-deep multiband Very Large Array (VLA) survey of the faint radio sky (COSMOS-XS): new constraints on the cosmic star formation history

Large scale structure and cosmolog

Kiloparsec-scale Imaging of the CO(1-0)-traced cold molecular gas reservoir in a z similar to 3.4 submillimeter galaxy

We present a high-resolution study of the cold molecular gas as traced by CO(1-0) in the unlensed z similar to 3.4 submillimeter galaxy SMM J13120+4242, using multiconfiguration observations with the Karl G. Jansky Very Large Array (JVLA). The gas reservoir, imaged on 0 ''.39 (similar to 3 kpc) scales, is resolved into two components separated by similar to 11 kpc with a total extent of 16 +/- 3 kpc. Despite the large spatial extent of the reservoir, the observations show a CO(1-0) FWHM linewidth of only 267 +/- 64 km s(-1). We derive a revised line luminosity of LCO(1-0)' = (10 +/- 3) x 10(10) K km s(-1) pc(2) and a molecular gas mass of M-gas = (13 +/- 3)x 10(10) (alpha(CO)/1) M-circle dot. Despite the presence of a velocity gradient (consistent with previous resolved CO(6-5) imaging), the CO(1-0) imaging shows evidence for significant turbulent motions that are preventing the gas from fully settling into a disk. The system likely represents a merger in an advanced stage. Although the dynamical mass is highly uncertain, we use it to place an upper limit on the CO-to-H-2 mass conversion factor a alpha(CO) of 1.4. We revisit the SED fitting, finding that this galaxy lies on the very massive end of the main sequence at z = 3.4. Based on the low gas fraction, short gas depletion time, and evidence for a central AGN, we propose that SMM J13120 is in a rapid transitional phase between a merger-driven starburst and an unobscured quasar. The case of SMM J13120 highlights how mergers may drive important physical changes in galaxies without pushing them off the main sequence.Galaxie

Cold Gas in High-z Galaxies: CO as Redshift Beacon

ASP Conference Series (ASPCS), Monograph 7Large scale structure and cosmolog

An ultradeep multiband VLA survey of the faint radio sky (COSMOS-XS): source catalog and number counts

Galaxie

An ALMA survey of CO in submillimetre galaxies: companions, triggering, and the environment in blended sources

We present ALMA observations of the mid-J 12CO emission from six single-dish selected 870-μm sources in the Extended Chandra Deep Field-South and UKIDSS Ultra-Deep Survey fields. These six single-dish submillimetre sources were selected based on previous ALMA continuum observations, which showed that each comprised a blend of emission from two or more individual submillimetre galaxies (SMGs), separated on 5–10 arcsec scales. The six single-dish submillimetre sources targeted correspond to a total of 14 individual SMGs, of which seven have previously measured robust optical/near-infrared spectroscopic redshifts, which were used to tune our ALMA observations. We detect CO(3–2) or CO(4–3) at z = 2.3–3.7 in 7 of the 14 SMGs, and in addition serendipitously detect line emission from three gas-rich companion galaxies, as well as identify four new 3.3 mm selected continuum sources in the six fields. Joint analysis of our CO spectroscopy and existing data suggests that 64(±18)percent of the SMGs in blended submillimetre sources are unlikely to be physically associated. However, three of the SMG fields (50 per cent) contain new, serendipitously detected CO-emitting (but submillimetre-faint) sources at similar redshifts to the 870 μm selected SMGs we targeted. These data suggest that the SMGs inhabit overdense regions, but that these are not sufficiently overdense on ∼100 kpc scales to influence the source blending given the short lifetimes of SMGs. We find that 21±12percent of SMGs have spatially distinct and kinematically close companion galaxies (∼8–150 kpc and ≲ 300 km s−1), which may have enhanced their star formation via gravitational interactions