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arXiv · 2210.16499

HectoMAP: The Complete Redshift Survey (Data Release 2)

Jubee Sohn·Margaret J. Geller·Ho Seong Hwang·Daniel G. Fabricant·Yousuke Utsumi·Ivana Damjanov
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Abstract

HectoMAP is a dense redshift survey of 95,403 galaxies based primarily on MMT spectroscopy with a median redshift $z = 0.345$. The survey covers 54.64 square degrees in a 1.5$^\circ$ wide strip across the northern sky centered at a declination of 43.25$^\circ$. We report the redshift, the spectral indicator D$_{n}$4000, and the stellar mass. The red selected survey is 81\% complete for 55,962 galaxies with $(g-r) > 1$ and $r <20.5$; it is 72\% complete for 32,908 galaxies with $(g-r) > 1$, $(r-i) > 0.5$ and $20.5 < r < 21.3$. Comparison of the survey basis SDSS photometry with the HSC-SSP photometry demonstrates that HectoMAP provides complete magnitude limited surveys based on either photometric system. We update the comparison between the HSC-SSP photometric redshifts with HectoMAP spectroscopic redshifts; the comparison demonstrates that the HSC-SSP photometric redshifts have improved between the second and third data releases. HectoMAP is a foundation for examining the quiescent galaxy population (63\% of the survey), clusters of galaxies, and the cosmic web. HectoMAP is completely covered by the HSC-SSP survey, thus enabling a variety of strong and weak lensing investigations.

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Jubee Sohn, Margaret J. Geller, Ho Seong Hwang, Daniel G. Fabricant, Yousuke Utsumi, Ivana Damjanov. 2022-10-29. HectoMAP: The Complete Redshift Survey (Data Release 2). https://doi.org/10.3847/1538-4357%2Facb925

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