The Chandra deep survey of the Hubble Deep Field North area. IV. An ultradeep image of the HDF-N

W. N. Brandt, A. E. Hornschemeier, D. M. Alexander, G. P. Garmire, D. P. Schneider, P. S. Broos, L. K. Townsley, M. W. Bautz, E. D. Feigelson, R. E. Griffiths

Research output: Contribution to journalArticle

97 Citations (Scopus)

Abstract

We present results from a 479.7 ks Chandra exposure of the Hubble Deep Field North (HDF-N) and its immediate vicinity. In this X-ray image, the deepest ever reported with a 0.5-2.0 keV flux limit of ≈4.9 × 10-17 ergs cm-2 s-1, four new HDF-N X-ray sources are detected, bringing the total number of such sources to 12. The new sources include two optically bright (R = 18.3-18.8) low-redshift (z < 0.15) galaxies, a Fanaroff-Riley I radio galaxy, and an edge-on spiral galaxy hosting either a powerful starburst and/or a low-luminosity active galactic nucleus (AGN). Notably, X-ray emission has now been detected from all luminous galaxies (Mv < -18) with z < 0.15 known in the HDF-N. We have also detected the remarkable microjansky radio source VLA J123642.09 + 621331.4, which is located just outside the HDF-N and has a likely redshift of z = 4.424. The observed X-ray emission supports the presence of an AGN in this object, and its X-ray-to-optical flux ratio (i.e., αox) is consistent with what is seen for low-redshift AGNs. We have detected X-ray variability from two of the previously known HDF-N X-ray sources, and spectral fitting shows clear evidence for X-ray absorption in the brightest X-ray source in the HDF-N, a z = 0.960 broad-line AGN with associated Mg II absorption. Stacking analyses of optically bright HDF-N galaxies not individually detected in X-rays have provided estimates of their average X-ray fluxes, and we find that the X-ray luminosities of "normal" spiral galaxies at z ≈ 0.5 are not more than a factor of ≈2 larger (per unit B-band luminosity) than those of spiral galaxies in the local universe (z < 0.01). This constrains models for the evolution of low-mass X-ray binary populations in galaxies in response to the declining cosmic star formation rate. Monte Carlo simulations support the validity of the stacking analyses and show that the Chandra Advanced CCD Imaging Spectrometer (ACIS) performs source detection well even with effective exposure times of ≈8 Ms.

Original languageEnglish (US)
Pages (from-to)1-20
Number of pages20
JournalAstronomical Journal
Volume122
Issue number1
DOIs
StatePublished - Jul 1 2001

Fingerprint

x rays
spiral galaxies
active galactic nuclei
galaxies
luminosity
stacking
radio
imaging spectrometers
radio galaxies
star formation rate
erg
charge coupled devices
spectrometer
universe
estimates
simulation
exposure

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Brandt, W. N. ; Hornschemeier, A. E. ; Alexander, D. M. ; Garmire, G. P. ; Schneider, D. P. ; Broos, P. S. ; Townsley, L. K. ; Bautz, M. W. ; Feigelson, E. D. ; Griffiths, R. E. / The Chandra deep survey of the Hubble Deep Field North area. IV. An ultradeep image of the HDF-N. In: Astronomical Journal. 2001 ; Vol. 122, No. 1. pp. 1-20.
@article{10f154f10efe4bc683034ad5f62191bb,
title = "The Chandra deep survey of the Hubble Deep Field North area. IV. An ultradeep image of the HDF-N",
abstract = "We present results from a 479.7 ks Chandra exposure of the Hubble Deep Field North (HDF-N) and its immediate vicinity. In this X-ray image, the deepest ever reported with a 0.5-2.0 keV flux limit of ≈4.9 × 10-17 ergs cm-2 s-1, four new HDF-N X-ray sources are detected, bringing the total number of such sources to 12. The new sources include two optically bright (R = 18.3-18.8) low-redshift (z < 0.15) galaxies, a Fanaroff-Riley I radio galaxy, and an edge-on spiral galaxy hosting either a powerful starburst and/or a low-luminosity active galactic nucleus (AGN). Notably, X-ray emission has now been detected from all luminous galaxies (Mv < -18) with z < 0.15 known in the HDF-N. We have also detected the remarkable microjansky radio source VLA J123642.09 + 621331.4, which is located just outside the HDF-N and has a likely redshift of z = 4.424. The observed X-ray emission supports the presence of an AGN in this object, and its X-ray-to-optical flux ratio (i.e., αox) is consistent with what is seen for low-redshift AGNs. We have detected X-ray variability from two of the previously known HDF-N X-ray sources, and spectral fitting shows clear evidence for X-ray absorption in the brightest X-ray source in the HDF-N, a z = 0.960 broad-line AGN with associated Mg II absorption. Stacking analyses of optically bright HDF-N galaxies not individually detected in X-rays have provided estimates of their average X-ray fluxes, and we find that the X-ray luminosities of {"}normal{"} spiral galaxies at z ≈ 0.5 are not more than a factor of ≈2 larger (per unit B-band luminosity) than those of spiral galaxies in the local universe (z < 0.01). This constrains models for the evolution of low-mass X-ray binary populations in galaxies in response to the declining cosmic star formation rate. Monte Carlo simulations support the validity of the stacking analyses and show that the Chandra Advanced CCD Imaging Spectrometer (ACIS) performs source detection well even with effective exposure times of ≈8 Ms.",
author = "Brandt, {W. N.} and Hornschemeier, {A. E.} and Alexander, {D. M.} and Garmire, {G. P.} and Schneider, {D. P.} and Broos, {P. S.} and Townsley, {L. K.} and Bautz, {M. W.} and Feigelson, {E. D.} and Griffiths, {R. E.}",
year = "2001",
month = "7",
day = "1",
doi = "10.1086/321135",
language = "English (US)",
volume = "122",
pages = "1--20",
journal = "Astronomical Journal",
issn = "0004-6256",
publisher = "IOP Publishing Ltd.",
number = "1",

}

The Chandra deep survey of the Hubble Deep Field North area. IV. An ultradeep image of the HDF-N. / Brandt, W. N.; Hornschemeier, A. E.; Alexander, D. M.; Garmire, G. P.; Schneider, D. P.; Broos, P. S.; Townsley, L. K.; Bautz, M. W.; Feigelson, E. D.; Griffiths, R. E.

In: Astronomical Journal, Vol. 122, No. 1, 01.07.2001, p. 1-20.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The Chandra deep survey of the Hubble Deep Field North area. IV. An ultradeep image of the HDF-N

AU - Brandt, W. N.

AU - Hornschemeier, A. E.

AU - Alexander, D. M.

AU - Garmire, G. P.

AU - Schneider, D. P.

AU - Broos, P. S.

AU - Townsley, L. K.

AU - Bautz, M. W.

AU - Feigelson, E. D.

AU - Griffiths, R. E.

PY - 2001/7/1

Y1 - 2001/7/1

N2 - We present results from a 479.7 ks Chandra exposure of the Hubble Deep Field North (HDF-N) and its immediate vicinity. In this X-ray image, the deepest ever reported with a 0.5-2.0 keV flux limit of ≈4.9 × 10-17 ergs cm-2 s-1, four new HDF-N X-ray sources are detected, bringing the total number of such sources to 12. The new sources include two optically bright (R = 18.3-18.8) low-redshift (z < 0.15) galaxies, a Fanaroff-Riley I radio galaxy, and an edge-on spiral galaxy hosting either a powerful starburst and/or a low-luminosity active galactic nucleus (AGN). Notably, X-ray emission has now been detected from all luminous galaxies (Mv < -18) with z < 0.15 known in the HDF-N. We have also detected the remarkable microjansky radio source VLA J123642.09 + 621331.4, which is located just outside the HDF-N and has a likely redshift of z = 4.424. The observed X-ray emission supports the presence of an AGN in this object, and its X-ray-to-optical flux ratio (i.e., αox) is consistent with what is seen for low-redshift AGNs. We have detected X-ray variability from two of the previously known HDF-N X-ray sources, and spectral fitting shows clear evidence for X-ray absorption in the brightest X-ray source in the HDF-N, a z = 0.960 broad-line AGN with associated Mg II absorption. Stacking analyses of optically bright HDF-N galaxies not individually detected in X-rays have provided estimates of their average X-ray fluxes, and we find that the X-ray luminosities of "normal" spiral galaxies at z ≈ 0.5 are not more than a factor of ≈2 larger (per unit B-band luminosity) than those of spiral galaxies in the local universe (z < 0.01). This constrains models for the evolution of low-mass X-ray binary populations in galaxies in response to the declining cosmic star formation rate. Monte Carlo simulations support the validity of the stacking analyses and show that the Chandra Advanced CCD Imaging Spectrometer (ACIS) performs source detection well even with effective exposure times of ≈8 Ms.

AB - We present results from a 479.7 ks Chandra exposure of the Hubble Deep Field North (HDF-N) and its immediate vicinity. In this X-ray image, the deepest ever reported with a 0.5-2.0 keV flux limit of ≈4.9 × 10-17 ergs cm-2 s-1, four new HDF-N X-ray sources are detected, bringing the total number of such sources to 12. The new sources include two optically bright (R = 18.3-18.8) low-redshift (z < 0.15) galaxies, a Fanaroff-Riley I radio galaxy, and an edge-on spiral galaxy hosting either a powerful starburst and/or a low-luminosity active galactic nucleus (AGN). Notably, X-ray emission has now been detected from all luminous galaxies (Mv < -18) with z < 0.15 known in the HDF-N. We have also detected the remarkable microjansky radio source VLA J123642.09 + 621331.4, which is located just outside the HDF-N and has a likely redshift of z = 4.424. The observed X-ray emission supports the presence of an AGN in this object, and its X-ray-to-optical flux ratio (i.e., αox) is consistent with what is seen for low-redshift AGNs. We have detected X-ray variability from two of the previously known HDF-N X-ray sources, and spectral fitting shows clear evidence for X-ray absorption in the brightest X-ray source in the HDF-N, a z = 0.960 broad-line AGN with associated Mg II absorption. Stacking analyses of optically bright HDF-N galaxies not individually detected in X-rays have provided estimates of their average X-ray fluxes, and we find that the X-ray luminosities of "normal" spiral galaxies at z ≈ 0.5 are not more than a factor of ≈2 larger (per unit B-band luminosity) than those of spiral galaxies in the local universe (z < 0.01). This constrains models for the evolution of low-mass X-ray binary populations in galaxies in response to the declining cosmic star formation rate. Monte Carlo simulations support the validity of the stacking analyses and show that the Chandra Advanced CCD Imaging Spectrometer (ACIS) performs source detection well even with effective exposure times of ≈8 Ms.

UR - http://www.scopus.com/inward/record.url?scp=17544403588&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=17544403588&partnerID=8YFLogxK

U2 - 10.1086/321135

DO - 10.1086/321135

M3 - Article

AN - SCOPUS:17544403588

VL - 122

SP - 1

EP - 20

JO - Astronomical Journal

JF - Astronomical Journal

SN - 0004-6256

IS - 1

ER -