arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0709.0859astro-ph
收藏

SNLS光谱学:Ia型超新星演化的检验

SNLS Spectroscopy: Testing for Evolution in Type Ia Supernovae

T. J. Bronder, I. M. Hook, P. Astier, D. Balam, C. Balland, S. Basa, R. G. Carlberg, A. Conley, D. Fouchez, J. Guy, D. A. Howell, J. D. Neill, R. Pain, K. Perre… 展开作者

T. J. Bronder, I. M. Hook, P. Astier, D. Balam, C. Balland, S. Basa, R. G. Carlberg, A. Conley, D. Fouchez, J. Guy, D. A. Howell, J. D. Neill, R. Pain, K. Perrett, C. J. Pritchet, N. Regnault, M. Sullivan, S. Baumont, S. Fabbro, M. Filliol, S. Perlmutter, P. Ripoche

摘要:

目的:我们提出了一个新的数据集的高红移Ia型超新星光谱的定量研究,观察在双子座望远镜在第一个34个月的超新星遗产调查。在此期间,观测到了123颗超新星候选者,其中87颗被确认为Ia型超新星,红移中值为z=0.720。从整个第二年的调查和第三年的一部分光谱(59个总SNe候选人与46个确认的SNe Ia)首次公布在这里。对该数据集进行的光谱测量用于确定这些遥远的SNe是否包含与当地观察到的相似的种群。方法:静息帧等效宽度和射血速度测量的四个光谱特征。相应的测量,提出了一组167光谱从24个低Z超新星Ia从文献。结果:我们发现在高红移处存在一个具有与附近SNe相似性质的样品。在低和高redsift的三个功能的测量分布之间没有显着差异。第四个特征显示了一个可能的差异,应该进一步研究。Ia型SNe属性和宿主星系形态之间的相关性也被发现在低和高Z是相似的,在每个宿主星系类,我们没有看到任何证据红移演化SN属性。提出了一种新的Ia型超新星的峰值强度与Si Ⅱ吸收的等效宽度之间的关系。我们证明,这种相关性减少了散射的Ia超新星光度距离的光变曲线形状光度校正,用于Ia型超新星宇宙学的方式一致。结论:我们表明,这个新的SNLS SNe Ia样本具有与附近物体相似的光谱特性。(节录)

英文摘要:

Aims: We present a quantitative study of a new data set of high redshift Type Ia supernovae spectra, observed at the Gemini telescopes during the first 34 months of the Supernova Legacy Survey. During this time 123 supernovae candidates were observed, of which 87 have been identified as SNe Ia at a median redshift of z=0.720. Spectra from the entire second year of the survey and part of the third year (59 total SNe candidates with 46 confirmed SNe Ia) are published here for the first time. The spectroscopic measurements made on this data set are used determine if these distant SNe comprise a population similar to those observed locally. Methods: Rest-frame equivalent width and ejection velocity measurements are made on four spectroscopic features. Corresponding measurements are presented for a set of 167 spectra from 24 low-z SNe Ia from the literature. Results: We show that there exists a sample at high redshift with properties similar to nearby SNe. No significant difference was found between the distributions of measurements at low and high redsift for three of the features. The fourth feature displays a possible difference that should be investigated further. Correlations between Type Ia SNe properties and host galaxy morphology were also found to be similar at low and high z, and within each host galaxy class we see no evidence for redshift-evolution in SN properties. A new correlation between SNe Ia peak magnitude and the equivalent width of SiII absorption is presented. We demonstrate that this correlation reduces the scatter in SNe Ia luminosity distances in a manner consistent with the lightcurve shape-luminosity corrections that are used for Type Ia SNe cosmology. Conclusions: We show that this new sample of SNLS SNe Ia has spectroscopic properties similar to nearby objects. (Abridged)

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑