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J/A+A/610/A53   Strong lensing star-forming galaxies with ALMA (Massardi+, 2018)

Chandra and ALMA observations of the nuclear activity in two strongly lensed star-forming galaxies. Massardi M., Enia A.F.M., Negrello M., Mancuso C., Lapi A., Vignali C., Gilli R., Burkutean S., Danese L., De Zotti G. <Astron. Astrophys. 610, A53 (2018)> =2018A&A...610A..53M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, radio ; Gravitational lensing Keywords: galaxies: active - gravitational lensing: strong - submillimeter: galaxies - galaxies: evolution - X-rays: galaxies Abstract: According to coevolutionary scenarios, nuclear activity and star formation play relevant roles in the early stages of galaxy formation. We aim at identifying them in high-redshift galaxies by exploiting high-resolution and high-sensitivity X-ray and millimeter-wavelength data to confirm the presence or absence of star formation and nuclear activity and describe their relative roles in shaping the spectral energy distributions and in contributing to the energy budgets of the galaxies. We present the data, model, and analysis in the X-ray and millimeter (mm) bands for two strongly lensed galaxies, SDP.9 (HATLAS J090740.0-004200) and SDP.11 (HATLAS J091043.1-000322), which we selected in the Herschel-ATLAS catalogs for their excess emission in the mid-IR regime at redshift ≥1.5. This emission suggests nuclear activity in the early stages of galaxy formation. We observed both of them with Chandra ACIS-S in the X-ray regime and analyzed the high-resolution mm data that are available in the ALMA Science Archive for SDP.9. By combining the information available in mm, optical, and X-ray bands, we reconstructed the source morphology. Both targets were detected in the X-ray, which strongly indicates highly obscured nuclear activity. ALMA observations for SDP.9 for the continuum and CO(6-5) spectral line with high resolution (0.02-arcsec corresponding to ∼65pc at the distance of the galaxy) allowed us to estimate the lensed galaxy redshift to a better accuracy than pre-ALMA estimates (1.5753±0.0003) and to model the emission of the optical, millimetric, and X-ray band for this galaxy. We demonstrate that the X-ray emission is generated in the nuclear environment, which strongly supports that this object has nuclear activity. On the basis of the X-ray data, we attempt an estimate of the black hole properties in these galaxies. By taking advantage of the lensing magnification, we identify weak nuclear activity associated with high-z galaxies with high star formation rates. This is useful to extend the investigation of the relationship between star formation and nuclear activity to two intrinsically less luminous high-z star-forming galaxies than was possible so far. Given our results for only two objects, they alone cannot constrain the evolutionary models, but provide us with interesting hints and set an observational path toward addressing the role of star formation and nuclear activity in forming galaxies. Description: We present high-resolution (<0.1arcsec) observations of SDP.9 (HATLAS J090740.0-004200), made with ALMA. Objects: ----------------------------------------------------------- RA (2000) DE Designation(s) ----------------------------------------------------------- 09 07 40.0 -00 42 00 SDP 9 = H-ATLAS J090740.0-004200 ----------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file list.dat 139 2 List of fits files fits/* 0 2 Individual fits files
Byte-by-byte Description of file: list.dat
Bytes Format Units Label Explanations
1- 9 F9.5 deg RAdeg Right Ascension of center (J2000) 10- 18 F9.5 deg DEdeg Declination of center (J2000) 20- 23 I4 --- Nx Number of pixels along X-axis 25- 28 I4 --- Ny Number of pixels along Y-axis 30- 31 I2 --- Nz ? Number of slides 33- 55 A23 --- Observation date 57- 63 F7.3 GHz Freq Observed frequency or lower value of frequency interval for the datacube 65- 71 F7.3 GHz BFreq ? Upper value of frequency interval for the datacube 73- 83 E11.6 Hz dFreq ? Frequency resolution for the datacube 85- 90 I6 Kibyte size Size of FITS file 92-105 A14 --- FileName Name of FITS file, in subdirectory fits 107-139 A33 --- Title Title of the FITS file
Acknowledgements: Marcella Massardi, massardi(at)
(End) Patricia Vannier [CDS] 09-Mar-2018
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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