Photometric calibration of the Supernova Legacy Survey fields
Photometric calibration of the Supernova Legacy Survey fields
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DOI：
10.1051/0004-6361/200912446
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发表时间：
2006-10
影响因子：
6.5
通讯作者：
N. Regnault;A. Conley;J. Guy;M. Sullivan;J. Cuillandre;P. Astier;C. Balland;S. Basa;R. Carlberg
中科院分区：
文献类型：
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作者：
N. Regnault;A. Conley;J. Guy;M. Sullivan;J. Cuillandre;P. Astier;C. Balland;S. Basa;R. Carlberg
目的：介绍超新星遗产调查(SNLS)场的光度定标。SNLS的目标是使用加拿大-法国-夏威夷望远镜(CFHT)上的1°2成像器MegaCam测量到SNE Ia的距离(0.3；z<；1)。影响测量光度定标的不确定度主导着测量关键测量的系统不确定度，即暗能量状态方程。SNLS的光度定标需要在成像仪上获得统一的响应，相对于相同波段中具有已知通量的标准，对每个调查波段(类似SDSS的UGRIZ波段)的科学场恒星进行定标，并将定标与UBVRI Landolt标准结合起来，UBVRI Landolt标准用于从产生宇宙学约束所需的文献中定标附近的SNE。方法：利用密集恒星场的抖动观测，绘制成像器光度响应的空间不均匀图。得到了朗道标准的测光零点。对仪器的线性度进行了研究。结果：我们发现成像器滤光片和光度响应不一致，并发布了校正图。我们给出了仪器的有效通带作为焦平面位置的函数的模型。我们为MegaCam定义了一个自然震级系统。结果表明，用分光光度标准星BD+174708代替织女星作为基本通量标准，可以减少系统学对星等通量关系的影响。我们为所有SNLS油田发布三级标准的UGRIZ目录。根据由加拿大国家研究委员会、法国国家科学研究中心L宇宙科学研究所和夏威夷大学运营的加拿大-法国-夏威夷望远镜的MegaPrime/MegaCam联合项目所获得的观测结果。这项工作的部分依据是加拿大天文数据中心制作的数据产品，该数据产品是加拿大-法国-夏威夷望远镜遗产调查的一部分，这是国家研究中心和国家科学研究中心的一个合作项目。表13-22和D.1-D.3也可以通过匿名ftp到cdsarc.u-strasbg.fr(130.79.128.5)或通过http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/506/999在疾控中心以电子形式获得
Aims: We present the photometric calibration of the Supernova Legacy Survey (SNLS) fields. The SNLS aims at measuring the distances to SNe Ia at (0.3 < z < 1) using MegaCam, the 1 deg2 imager on the Canada-France-Hawaii Telescope (CFHT). The uncertainty affecting the photometric calibration of the survey dominates the systematic uncertainty of the key measurement of the survey, namely the dark energy equation of state. The photometric calibration of the SNLS requires obtaining a uniform response across the imager, calibrating the science field stars in each survey band (SDSS-like ugriz bands) with respect to standards with known flux in the same bands, and binding the calibration to the UBVRI Landolt standards used to calibrate the nearby SNe from the literature necessary to produce cosmological constraints. Methods: The spatial non-uniformities of the imager photometric response are mapped using dithered observations of dense stellar fields. Photometric zero-points against Landolt standards are obtained. The linearity of the instrument is studied. Results: We show that the imager filters and photometric response are not uniform and publish correction maps. We present models of the effective passbands of the instrument as a function of the position on the focal plane. We define a natural magnitude system for MegaCam. We show that the systematics affecting the magnitude-to-flux relations can be reduced if we use the spectrophotometric standard star BD +17 4708 instead of Vega as a fundamental flux standard. We publish ugriz catalogs of tertiary standards for all the SNLS fields. Based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. Tables 13-22 and D.1-D.3 are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/506/999