대표연구 논문 실적
RVSNUpy: A Python Package for Spectroscopic Redshift Measurement Based on Cross Correlation
발행년도
20250604
저자
Taewan Kim, Jubee Sohn, Ho Seong Hwang
저널
ASTRONOMICAL JOURNAL
작성자
전지현
작성일
2025-06-10
조회
3
Abstract
We introduce RVSNUpy, a new Python package designed to measure spectroscopic redshifts. Based on inverse
variance-weighted cross correlation, RVSNUpy determines redshifts by comparing observed spectra with various
rest-frame template spectra. We test the performance of RVSNUpy based on ∼6000 objects in the HectoMAP
redshift survey observed with both the Sloan Digital Sky Survey (SDSS) and MMT/Hectospec. We demonstrate
that a slight redshift offset (∼40 km s−1) between the SDSS and MMT/Hectospec measurements reported from
previous studies results from the small offsets in the redshift template spectra used for SDSS and Hectospec
reductions. We construct a universal set of template spectra, including empirical SDSS template spectra, carefully
calibrated to the rest frame. Our test for the HectoMAP objects with duplicated observations shows that
RVSNUpy with the universal template spectra yields homogeneous redshifts for spectra obtained with different
spectrographs. We highlight that RVSNUpy is a powerful redshift measurement tool for current and future large
scale spectroscopy surveys, including A-SPEC, DESI, 4MOST, and the Subaru Prime Focus Spectrograph.
https://DOI.org/10.3847/1538-3881/add348
We introduce RVSNUpy, a new Python package designed to measure spectroscopic redshifts. Based on inverse
variance-weighted cross correlation, RVSNUpy determines redshifts by comparing observed spectra with various
rest-frame template spectra. We test the performance of RVSNUpy based on ∼6000 objects in the HectoMAP
redshift survey observed with both the Sloan Digital Sky Survey (SDSS) and MMT/Hectospec. We demonstrate
that a slight redshift offset (∼40 km s−1) between the SDSS and MMT/Hectospec measurements reported from
previous studies results from the small offsets in the redshift template spectra used for SDSS and Hectospec
reductions. We construct a universal set of template spectra, including empirical SDSS template spectra, carefully
calibrated to the rest frame. Our test for the HectoMAP objects with duplicated observations shows that
RVSNUpy with the universal template spectra yields homogeneous redshifts for spectra obtained with different
spectrographs. We highlight that RVSNUpy is a powerful redshift measurement tool for current and future large
scale spectroscopy surveys, including A-SPEC, DESI, 4MOST, and the Subaru Prime Focus Spectrograph.
https://DOI.org/10.3847/1538-3881/add348
