J/A+A/557/A82 Near-IR polarimetry of Galactic center sources (Buchholz+, 2013) ================================================================================ Ks- and Lp-band polarimetry on stellar and bow-shock sources in the Galactic Center. Buchholz R.M., Witzel G., Schodel R., Eckart A. =2013A&A...557A..82B ================================================================================ ADC_Keywords: Stars, nearby ; Infrared sources ; Photometry, infrared ; Polarization Keywords: Galaxy: center - polarization - dust, extinction - infrared: stars Abstract: Infrared observations of the Galactic center (GC) provide a unique opportunity to study stellar and bow-shock polarization effects in a dusty environment. The goals of this work are to present new Ks- and Lp-band polarimetry on an unprecedented number of sources in the central parsec of the GC, thereby expanding our previous results in the H- and Ks-bands. We use AO-assisted Ks- and Lp-band observations, obtained at the ESO VLT. High precision photometry and the new polarimetric calibration method for NACO allow us to map the polarization in a region of 8"x25" (Ks) resp. 26"x28" (Lp). These are the first polarimetric observations of the GC in the Lp-band in 30 years, with vastly improved spatial resolution compared to previous results. This allows resolved polarimetry on bright bow-shock sources in this area for the first time at this wavelength. Description: This table contains the H-, Ks-, and Lp-band polarization of sources in the Galactic Center. For each source, the offset in Right Ascension and Declination as well as the projected distance from Sgr A* are given (in arcsec). The table also lists the source brightness in magnitudes in the H-, Ks-, and Lp-band for orientation. This table contains the data obtained in our previous study, Buchholz et al. 2011 (J/A+A/534/A117), in addition to the new results. Not every source is contained in all data-sets (one H-band, three Ks-band with different fields-of-view, one Lp-band). Entries with the value " - " indicate that the source is not contained in the respective data-set. Polarization degrees are given in percent, polarization angles in degrees. The data is combined from different epochs, so a small number of very fast moving sources may be listed separately for each data-set. Objects: ----------------------------------------------------- RA (2000) DE Designation(s) ----------------------------------------------------- 17 45 40.04 -29 00 28.2 SgrA* = NAME Sgr A* ----------------------------------------------------- File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file pollist.dat 130 557 H, Ks and Lp-band polarization parameters (tableA1) -------------------------------------------------------------------------------- See also: J/A+A/499/483 : sources in galactic center NIR observations (Buchholz+, 2009) J/A+A/502/91 : Proper motions of stars near SgrA* (Schoedel+, 2009) J/A+A/511/A18 : NIR observations of stars near SgrA* (Schoedel+, 2010) J/ApJ/727/L36 : 1.3mm VLBI observations of Sagittarius A* (Fish+, 2011) J/A+A/534/A117 : NIR polarimetry of sources near SgrA* (Buchholz+, 2011) Byte-by-byte Description of file: pollist.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- Seq Source number 5- 10 F6.2 arcsec oRA Right ascension offset from Sgr A* (1) 12- 17 F6.2 arcsec oDE Declination offset from Sgr A* (1) 19- 23 F5.2 arcsec Rp Projected distance from Sgr A* 25- 28 F4.1 mag Ksmag ?=- Apparent Ks-band magnitude 30- 32 F3.1 mag e_Ksmag ?=- Error of Ks-band magnitude 34- 37 F4.1 mag Hmag ?=- Apparent H-band magnitude 39- 41 F3.1 mag e_Hmag ?=- Error of H-band magnitude 43- 46 F4.1 mag Lpmag ?=- Apparent Lp-band magnitude 48- 50 F3.1 mag e_Lpmag ?=- Error of Lp-band magnitude 52- 55 F4.1 % pK1 ?=- Ks-band polarization degree (2) 57- 59 F3.1 % e_pK1 ?=- Error of pK1 61- 63 I3 % PAK1 [-90/90]?=- K-band polarization angle 65- 66 I2 % e_PAK1 ?=- Error of PAK1 68- 71 F4.1 % pK2 ?=- K-band polarization degree (2) 73- 75 F3.1 % e_pK2 ?=- Error of pK2 77- 79 I3 % PAK2 [-90/90]?=- K-band polarization angle 81- 82 I2 % e_PAK2 ?=- Error of PAK2 84- 87 F4.1 % pK3 ?=- K-band polarization degree (2) 89- 91 F3.1 % e_pK3 ?=- Error of pK3 93- 95 I3 deg PAK3 [-90/90]?=- K-band polarization angle 97- 98 I2 deg e_PAK3 ?=- Error of PAK3 100-103 F4.1 % pH ?=- H-band polarization degree (2) 105-107 F3.1 % e_pH ?=- Error of pH 109-111 I3 deg PAH [-90/90]?=- H-band polarization angle 113-114 I2 deg e_PAH ?=- Error of PAH 116-119 F4.1 % pLp ?=- Lp-band (3.5{mu}m) polarization degree (2) 121-123 F3.1 % e_pLp ?=- Error of pLp 125-127 I3 deg PALp [-90/90]?=- Lp-band polarization angle 129-130 I2 deg e_PALp ?=- Error of PALp -------------------------------------------------------------------------------- Note (1): Offsets from SgrA* at 17:45:40.036-29:00:28.17 (J2000). Note (2): the observations dates are: H = 2004-06-12 (30 exposures) K1 = 2009-05-18 (143 exposures) K2 = 2007-04-03 (70 exposures) K3 = 2011-03-19 (37 exposures) L = 2011-03-17 (26 exposures) -------------------------------------------------------------------------------- Acknowledgements: Dr. Rainer M. Buchholz, Rainer_Buchholz2001(at)yahoo.de Universita zu Kon, Germany ================================================================================ (End) Rainer Buchholz [Univ. zu Koln], Patricia Vannier [CDS] 10-Sep-2013