Access to Astronomical Catalogues

← Click to display the menu
J/MNRAS/472/2085   ALHAMBRA fields type-I AGN with ELDAR (Chaves-Montero+, 2017)

ELDAR, a new method to identify AGN in multi-filter surveys: the ALHAMBRA test-case. Chaves-Montero J., Bonoli S., Salvato M., Greisel N., Diaz-Garcia L.A., Lopez-Sanjuan C., Viironen K., Fernandez-Soto A., Povic M., Ascaso B., Arnalte-Mur P., Masegosa J., Matute I., Marquez I., Cenarro A. J., Abramo L.R., Ederoclite A., Alfaro E.J. <Mon. Not. R. Astron. Soc. 472, 2085 (2017)> =2017MNRAS.472.2085C (SIMBAD/NED BibCode)
ADC_Keywords: QSOs ; Spectrophotometry ; Redshifts ; Surveys Keywords: methods: data analysis - techniques: photometric - surveys - galaxies: active - galaxies: distances and redshifts - quasars: emission lines Abstract: We present ELDAR, a new method that exploits the potential of medium- and narrow-band filter surveys to securely identify active galactic nuclei (AGN) and determine their redshifts. Our methodology improves on traditional approaches by looking for AGN emission lines expected to be identified against the continuum, thanks to the width of the filters. To assess its performance, we apply ELDAR to the data of the ALHAMBRA survey, which covered an effective area of 2.38deg2 with 20 contiguous medium-band optical filters down to F814W=24.5. Using two different configurations of ELDAR in which we require the detection of at least 2 and 3 emission lines, respectively, we extract two catalogues of type-I AGN. The first is composed of 585 sources (79% of them spectroscopically-unknown) down to F814W=22.5 at zphot>1, which corresponds to a surface density of 209 deg-2. In the second, the 494 selected sources (83% of them spectroscopically-unknown) reach F814W=23 at zphot>1.5, for a corresponding number density of 176deg-2. Then, using samples of spectroscopically-known AGN in the ALHAMBRA fields, for the two catalogues we estimate a completeness of 73% and 67%, and a redshift precision of 1.01% and 0.86% (with outliers fractions of 8.1% and 5.8%). At z>2, where our selection performs best, we reach 85% and 77% completeness and we find no contamination from galaxies. Description: The catalogues ALH2L and ALH3L contain type-I AGN in the ALHAMBRA fields identified by using the 2- and 3-lines mode of ELDAR with the publicly available multi-band data of the ALHAMBRA survey, respectively, and they contain 585 and 494 sources. For each type-I AGN coordinates, redshift, best-fit template, PSF ALHAMBRA magnitudes, Stellarity, and properties of the AGN emission lines detected by ELDAR are given. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file alh2l.dat 530 585 ALH2L catalogue alh3l.dat 530 494 ALH3L catalogue
See also: J/AJ/139/1242 : ALHAMBRA photometric system (Villegas+, 2010) J/MNRAS/441/2891 : ALHAMBRA Survey (Molino+, 2014) J/MNRAS/435/3444 : ALHAMBRA survey morphological catalogue (Povic+, 2013) J/MNRAS/452/549 : ALHAMBRA survey galaxy clusters and groups (Ascaso+, 2015) Byte-by-byte Description of file: alh2l.dat alh3l.dat
Bytes Format Units Label Explanations
1- 8 A8 --- Name Identification number (ALHXLYYY) (1) 10- 17 F8.4 deg RAdeg Right ascension (J2000) 19- 26 F8.4 deg DEdeg Declination (J2000) 28- 32 F5.3 --- z Photometric redshift 34 I1 --- Mask [0,1] Mask (2) 36- 37 I2 --- Temp [1/12] Best-fit extragalactic template (3) 39- 42 F4.2 --- ExtB Best-fit colour excess 44- 49 F6.3 mag F814W F814W magnitude (4) 51- 55 F5.3 mag e_F814W F814W uncertainty (4) 57- 60 F4.2 --- Stell [0,1] Stellarity (1 = point-like sources, 0 = extended sources) 62- 68 F7.3 mag F365W ?=-99.000 F365W magnitude 70- 76 F7.3 mag e_F365W ?=-99.000 F365W uncertainty 78- 84 F7.3 mag F396W ?=-99.000 F396W magnitude 86- 92 F7.3 mag e_F396W ?=-99.000 F396W uncertainty 94-100 F7.3 mag F427W ?=-99.000 F427W magnitude 102-108 F7.3 mag e_F427W ?=-99.000 F427W uncertainty 110-116 F7.3 mag F458W ?=-99.000 F458W magnitude 118-124 F7.3 mag e_F458W ?=-99.000 F458W uncertainty 126-132 F7.3 mag F489W ?=-99.000 F489W magnitude 134-140 F7.3 mag e_F489W ?=-99.000 F489W uncertainty 142-148 F7.3 mag F520W ?=-99.000 F520W magnitude 150-156 F7.3 mag e_F520W ?=-99.000 F520W uncertainty 158-164 F7.3 mag F551W ?=-99.000 F551W magnitude 166-172 F7.3 mag e_F551W ?=-99.000 F551W uncertainty 174-180 F7.3 mag F582W ?=-99.000 F582W magnitude 182-188 F7.3 mag e_F582W ?=-99.000 F582W uncertainty 190-196 F7.3 mag F613W ?=-99.000 F613W magnitude 198-204 F7.3 mag e_F613W ?=-99.000 F613W uncertainty 206-212 F7.3 mag F644W ?=-99.000 F644W magnitude 214-220 F7.3 mag e_F644W ?=-99.000 F644W uncertainty 222-228 F7.3 mag F675W ?=-99.000 F675W magnitude 230-236 F7.3 mag e_F675W ?=-99.000 F675W uncertainty 238-244 F7.3 mag F706W ?=-99.000 F706W magnitude 246-252 F7.3 mag e_F706W ?=-99.000 F706W uncertainty 254-260 F7.3 mag F737W ?=-99.000 F737W magnitude 262-268 F7.3 mag e_F737W ?=-99.000 F737W uncertainty 270-276 F7.3 mag F768W ?=-99.000 F768W magnitude 278-284 F7.3 mag e_F768W ?=-99.000 F768W uncertainty 286-292 F7.3 mag F799W ?=-99.000 F799W magnitude 294-300 F7.3 mag e_F799W ?=-99.000 F799W uncertainty 302-308 F7.3 mag F830W ?=-99.000 F830W magnitude 310-316 F7.3 mag e_F830W ?=-99.000 F830W uncertainty 318-324 F7.3 mag F861W ?=-99.000 F861W magnitude 326-332 F7.3 mag e_F861W ?=-99.000 F861W uncertainty 334-340 F7.3 mag F892W ?=-99.000 F892W magnitude 342-348 F7.3 mag e_F892W ?=-99.000 F892W uncertainty 350-356 F7.3 mag F923W ?=-99.000 F923W magnitude 358-364 F7.3 mag e_F923W ?=-99.000 F923W uncertainty 366-372 F7.3 mag F954W ?=-99.000 F954W magnitude 374-380 F7.3 mag e_F954W ?=-99.000 F954W uncertainty 382-388 F7.3 mag FJ ?=-99.000 NIR-J magnitude 390-396 F7.3 mag e_FJ ?=-99.000 NIR-J uncertainty 398-404 F7.3 mag FH ?=-99.000 NIR-H magnitude 406-412 F7.3 mag e_FH ?=-99.000 NIR-H uncertainty 414-420 F7.3 mag FKs ?=-99.000 NIR-Ks magnitude 422-428 F7.3 mag e_FKs ?=-99.000 NIR-Ks uncertainty 430-431 I2 --- line1 Band where the OVI+Lyman beta complex is detected (5) 433-438 F6.3 [-] log(SNRl1) log_10(SNR) in the band where the OVI+Lyman beta complex is detected 440-445 F6.3 [-] log(Slin1) log_10(Slin) in the band where the OVI+Lyman beta complex is detected 447-448 I2 --- line2 Band where the Lyman alpha line is detected (5) 450-455 F6.3 [-] log(SNRl2) log_10(SNR) in the band where the Lyman alpha line is detected 457-462 F6.3 [-] log(Slin2) log_10(Slin) in the band where the Lyman alpha line is detected 464-465 I2 --- line3 Band where the SiIV+OIV complex is detected (5) 467-472 F6.3 [-] log(SNRl3) log_10(SNR) in the band where the SiIV+OIV complex is detected 474-479 F6.3 [-] log(Slin3) log_10(Slin) in the band where the SiIV+OIV complex is detected 481-482 I2 --- line4 Band where the CIV line is detected (5) 484-489 F6.3 [-] log(SNRl4) log_10(SNR) in the band where the CIV line is detected 491-496 F6.3 [-] log(Slin4) log_10(Slin) in the band where the CIV line complex is detected 498-499 I2 --- line5 Band where the CIII] line is detected (5) 501-506 F6.3 [-] log(SNRl5) log_10(SNR) in the band where the CIII] line is detected 508-513 F6.3 [-] log(Slin5) log_10(Slin) in the band where the CIII] line is detected 515-516 I2 --- line6 Band where the MgII line is detected (5) 518-523 F6.3 [-] log(SNRl6) log_10(SNR) in the band where the MgII line is detected 525-530 F6.3 [-] log(Slin6) log_10(Slin) in the band where the MgII line is detected (5)
Note (1): The format is ALHXLYYY, where the value of X is 2 and 3 for the ALH2L and ALH3L catalogues, respectively, and YYY is the number of the object. The IDs are ranked according to zphot. Note (2): ALHAMBRA angular mask of Arnalte-Mur et al. (2014MNRAS.441.1783A). It describes the sky area which has been reliably observed as follows: 1 = inside the mask 0 = outside the mask Note (3): Extragalactic templates that we introduce in LePHARE as follows: --------------------------------------------------------------- Index Template Class References --------------------------------------------------------------- 1 = I2249170TQSO1_30 Quasar 30% + Gal. 70% [1] 2 = I2249160TQSO1_40 Quasar 40% + Gal. 60% [1] 3 = I2249150TQSO1_50 Quasar 50% + Gal. 50% [1] 4 = I2249140TQSO1_60 Quasar 60% + Gal. 40% [1] 5 = plI2249130TQSO170 Quasar 70% + Gal. 30% [1] 6 = plI2249120TQSO180 Quasar 80% + Gal. 20% [1] 7 = plQSODR2029t0 Quasar low lum. [1] 8 = pl_QSOH Quasar high lum. [1] 9 = pl_TQSO1 Quasar high IR lum. [1] 10 = qso-0.2_84 Quasar synthetic [2] 11 = QSO_VVDS Quasar [3] 12 = QSO_SDSS Quasar [4] --------------------------------------------------------------- References. [1] Salvato et al. (2009ApJ...690.1250S) [2] LePHARE distribution [3] VVDS composite (Gavignaud et al., 2006, Cat. J/A+A/457/79) [4] SDSS composite (Vanden Berk et al., 2001AJ....122..549V) Templates starting with pl are extended into the UV using a power law (see Salvato et al., 2009ApJ...690.1250S). Note (4): The F814W ALHAMBRA band is a synthetic band that corresponds to the HST/ACD F814W band. It was employed to create the ALHAMBRA detection images. The signal-to-noise ratio in the detection band is 1/e_F814W. Note (5): ALHAMBRA band where AGN emission lines fall. It is 99 for no detections and 0 for lines outside the ALHAMBRA wavelength range. For detected lines we include the SNR in the line that they fall and the significance with which the line is detected, Slin.
Acknowledgements: Jonas Chaves-Montero, jonaschavesmontero22(at)gmail.com
(End) Jonas Chaves-Montero [CEFCA, Spain], Patricia Vannier [CDS] 29-Aug-2017
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

catalogue service

© UDS/CNRS

Contact