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(Ultra) Luminous Infrared Galaxies ((U)LIRGs) are objects characterized by their extreme infrared (8-1000 $mu$m) luminosities ($L_{LIRG}>10^{11} $L$_odot$ and $L_{ULIRG}>10^{12}$ L$_odot$). The Herschel Comprehensive ULIRG Emission Survey (HerCULES; PI van der Werf) presents a representative flux-limited sample of 29 (U)LIRGs that spans the full luminosity range of these objects (10$^{11}leq L_odot geq10^{13}$). With the emph{Herschel Space Observatory}, we observe [CII] 157 $mu$m, [OI] 63 $mu$m, and [OI] 145 $mu$m line emission with PACS, CO J=4-3 through J=13-12, [CI] 370 $mu$m, and [CI] 609 $mu$m with SPIRE, and low-J CO transitions with ground-based telescopes. The CO ladders of the sample are separated into three classes based on their excitation level. In 13 of the galaxies, the [OI] 63 $mu$m emission line is self absorbed. Comparing the CO excitation to the IRAS 60/100 $mu$m ratio and to far infrared luminosity, we find that the CO excitation is more correlated to the far infrared colors. We present cooling budgets for the galaxies and find fine-structure line flux deficits in the [CII], [SiII], [OI], and [CI] lines in the objects with the highest far IR fluxes, but do not observe this for CO $4leq J_{upp}leq13$. In order to study the heating of the molecular gas, we present a combination of three diagnostic quantities to help determine the dominant heating source. Using the CO excitation, the CO J=1-0 linewidth, and the AGN contribution, we conclude that galaxies with large CO linewidths always have high-excitation CO ladders, and often low AGN contributions, suggesting that mechanical heating is important.
We present the first complete CO J=3-2 map of the nearby grand-design spiral galaxy M51 (NGC 5194), at a spatial resolution of ~600 pc, obtained with the HARP-B instrument on the James Clerk Maxwell Telescope. The map covers the entire optical galaxy disk and out to the companion NGC 5195, with CO J=3-2 emission detected over an area of ~9x6 (~21x14 kpc). We describe the CO J=3-2 integrated intensity map and combine our results with maps of CO J=2-1, CO J=1-0 and other data from the literature to investigate the variation of the molecular gas, atomic gas and polycyclic aromatic hydrocarbon (PAH) properties of M51 as a function of distance along the spiral structure on sub-kpc scales. We find that for the CO J=3-2 and CO J=2-1 transitions there is a clear difference between the variation of arm and inter-arm emission with galactocentric radius, with the inter-arm emission relatively constant with radius and the contrast between arm and inter-arm emission decreasing with radius. For CO J=1-0 and HI the variation with radius shows a similar trend for the arm and inter-arm regions, and the arm-inter-arm contrast appears relatively constant with radius. We investigate the variation of CO line ratios (J=3-2/2-1, J=2-1/1-0 and J=3-2/1-0) as a function of distance along the spiral structure. Line ratios are consistent with the range of typical values for other nearby galaxies in the literature. The highest CO J=3-2/2-1 line ratios are found in the central ~1 kpc and in the spiral arms and the lowest line ratios in the inter-arm regions.We find no clear evidence of a trend with radius for the spiral arms but for the inter-arm regions there appears to be a trend for all CO line ratios to increase with radius. We find a strong relationship between the ratio of CO J=3-2 intensity to stellar continuum-subtracted 8mu PAH surface brightness and the CO J=3-2 intensity that appears to vary with radius.
An integrated filterbank (IFB) in combination with microwave kinetic inductance detectors (MKIDs), both based on superconducting resonators, could be used to make broadband submillimeter imaging spectrographs that are compact and flexible. In order t o investigate the possibility of adopting an IFB configuration for DESHIMA (Delft SRON High-redshift Mapper), we study the basic properties of a coplanar-waveguide-based IFB using electromagnetic simulation. We show that a coupling efficiency greater than 1/2 can be achieved if transmission losses are negligible. We arrive at a practical design for a 9 pixel x 920 color 3 dimensional imaging device that fits on a 4 inch wafer, which instantaneously covers multiple submillimeter telluric windows with a dispersion of f/df = 1000.
Context. The study of high redshift Tully-Fisher relations (TFRs) is limited by the use of long slit spectrographs, rest frame B band and star formation selected galaxies. Aims. We try to circumvent these issues by using integral field spectroscopy ( SINFONI), by studying the rest frame K band and stellar mass TFR, and by selecting targets without a bias to strongly star forming galaxies. In this paper, we demonstrate our methods on our best case. This galaxy, F257, at z=2.03, was selecte from a sample of candidate high redshift large disk galaxies in the Hubble Deep Field South that were selected with photometric and morphological criteria. Methods. We used SINFONI at the VLT to obtain an integral field spectrum of the Halpha line and hence a velocity field and rotation curve. We also use UBVIJHK+IRAC band photometry to determine a stellar photometric mass. Results. We find that F257 is indistinguishable from local late type galaxies in many respects: it has a regular velocity field, increasing velocity disperion towards its center, its rotation curve flattens at 1-2 disk scale lengths, it has the same specific angular momentum as local disks, its properties are consistent with the local K band TFR. Although mainly rotationally supported, its gas component is dynamically heated with respect to local galaxies (V/sigma_z ~ 4) and it is offset from the local stellar mass TFR at the 2sigma level. But, this offset depends on the SED modeling parameters. In particular, for a 2-component star formation history (SFH), F257 is in agreement with the local stellar mass TFR. F257 is then a nearly (~75%) maximum disk. The dynamical properties of F257 are more like those of local galaxies than those of any other galaxy at similar redshift observed to date. However, the gas-to-stellar mass ratio is unusally large: 2.5.
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