Faint Source Counts from Off-source Fluctuation Analysis on Chandra Observations of the Hubble Deep Field-North
Abstract
We report the results of fluctuation analysis of the off-source field from the 1 Million second Chandra observation of the Hubble Deep Field-North (HDF-N). The distribution of the counts in cells has been compared with the expectations from the Log N - Log S model to constrain the behavior of the source number density down to a factor of several lower than the source-detection limit. Our results show that the number counts in the soft band (0.5-2 [keV]) continue to grow down to Sx = 7e-18 [erg s^{-1} cm^{-2}], possibly suggesting the emergence of a new population and agree well with a prediction of star forming galaxies by Ptak et al. (2001). For the hard band (2-10 keV), the fluctuation analysis can loosely constrain the source counts fainter than the detection limit and we found an upper limit of 10000 [srcs deg^{-2}] at Sx=2e-16 [erg s^{-1}cm^{-2}].
Keywords
Cite
@article{arxiv.astro-ph/0111393,
title = {Faint Source Counts from Off-source Fluctuation Analysis on Chandra Observations of the Hubble Deep Field-North},
author = {Takamitsu Miyaji and Richard E. Griffiths},
journal= {arXiv preprint arXiv:astro-ph/0111393},
year = {2009}
}
Comments
7 Pages 2 Figures. Fig. 2 replaced due to a minor labeling error. This version is more updated than the journal artilcle and includes color figures