J/A+A/550/A62 DIBs from Baade's window bulge clump giants (Chen+, 2013) ================================================================================ Extracting interstellar diffuse absorption bands from cool star spectra. Application to bulge clump giants in Baade's window. Chen H.-C., Lallement R., Babusiaux C., Puspitarini L., Bonifacio P., Hill V. =2013A&A...550A..62C ================================================================================ ADC_Keywords: Stars, giant; Equivalent widths Keywords: ISM: lines and bands - dust, extinction - ISM: structure - ISM: molecules - stars: late-type - methods: data analysis Abstract: Interstellar (IS) absorption lines or diffuse bands are usually extracted from early-type star spectra because they are characterized by smooth continua. However, this introduces a strong limitation on the number of available targets, and reduces potential studies of the IS matter and the use of absorptions for cloud mapping. We have developed a new and automated fitting method appropriate to interstellar (IS) absorptions in the spectra of cool stars that possess stellar atmospheric parameters. We applied this method to the extraction of three diffuse interstellar bands (DIBs) in high resolution VLT FLAMES/GIRAFFE spectra of red-clump stars from the bulge. By combining all stellar synthetic spectra, HITRAN-LBLRTM atmospheric transmission spectra and diffuse band empirical absorption profiles, we determined the 6196.0, 6204.5, and 6283.8{AA} DIB strength toward the 219 target stars and discuss the sources of uncertainties. To test the sensitivity of the DIB extraction, we compared all three results and compared the DIB equivalent widths (EWs) with the reddening derived from an independent extinction map based on OGLE photometric data. We also derived the three independent color excess estimates based on the DIB strengths and average linear correlation coefficients previously established in the solar neighborhood and compared with the OGLE photometric results. Description: We used the sample of 219 bulge red clump giants of Hill et al. (2011, Cat. J/A+A/534/A80). Those stars were observed with FLAMES/GIRAFFE at the VLT and are located within a 12-arcmin radius field in Baade's Window (l=0.8, b=-4). We used here the spectra obtained with the GIRAFFE HR13 setup, leading to a resolution of R=22500 and a spectral coverage spanning 6120 to 6405{AA}, which contains three well known diffuse bands. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table3.dat 70 219 Stellar data and measurement of equivalent widths -------------------------------------------------------------------------------- See also: II/149 : Diffuse Interstellar Band Measurements (Snow+ 1977) J/MNRAS/358/563 : Diffuse Interstellar Bands in 49 stars (Megier+, 2005) J/A+A/429/559 : Diffuse Interstellar Bands in NGC 1448 (Sollerman+, 2005) J/ApJ/705/32 : Diffuse interstellar bands from HD 183143 (Hobbs+, 2009) J/ApJ/708/1628 : Diffuse interstellar bands. IV. (McCall+, 2010) J/A+A/544/A136 : Diffuse Interstellar Bands in 150 stars (Raimond+, 2012) J/A+A/550/A108 : DIB in VLT-FLAMES Tarantula Survey (van Loon+, 2013) J/A+A/534/A80 : Baade's window bulge clump giants metallicities (Hill+, 2011) Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 3 I3 --- Star [1/219] Star sequential number, as in Hill et al., 2011, Cat. J/A+A/534/A80 5- 10 I6 --- Ogle OGLE number, BUL-SC45 NNNNNN, from Paczynski et al., 1999, Cat. J/AcA/49/319 12- 15 I4 K Teff Effective temperature 17- 20 F4.2 [cm/s2] logg Surface gravity 22- 24 F3.1 km/s Vturb Microturbulent velocity 26- 30 F5.2 [Sun] [Fe/H] Metallicity 32- 36 F5.3 mag E(B-V) Colour excess (1) 38- 40 I3 0.1pm W(6196) DIB6196{AA} equivalent width before correction 42- 43 I2 0.1pm W(6196)c DIB6196{AA} equivalent width after correction 45- 46 I2 0.1pm e_W(6196)c rms uncertainty on W(6196) and W(6196)c 48- 50 I3 0.1pm W(6204) DIB6204{AA} equivalent width before correction 52- 54 I3 0.1pm W(6204)c ? DIB6204{AA} equivalent width after correction 56- 57 I2 0.1pm e_W(6204)c ? rms uncertainty on W(6204) and W(6204)c 59- 62 I4 0.1pm W(6284) DIB6284{AA} equivalent width before correction 64- 67 I4 0.1pm W(6284)c ? DIB6284{AA} equivalent width after correction 69- 70 I2 0.1pm e_W(6284)c ? rms uncertainty on W(6284) and W(6284)c -------------------------------------------------------------------------------- Note (1): derived from Sumi (2004MNRAS.349..193S) by interpolation. -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Patricia Vannier [CDS] 30-Apr-2013