### Abstract

We use 90 quasars detected by their Lyα emission to well-defined flux limits in the Palomar Transit Grism Survey to derive the luminosity function of quasars in the redshift range 2.75-4.75. Application of the V/V_{max} test yields 〈V_{e}/V_{a}〉=0.377±0.026, corresponding to a nonuniform distribution in comoving coordinates, such that the space density decreases with redshift. The luminosity function appears to be well represented by a power law with a slope corresponding to a factor of 5.6 per magnitude. We discuss and define the relationship between the line luminosity function and the continuum luminosity function of quasars. The space density for M_{B}<-26 decreases by a factor of 2.7 per unit redshift beyond z=2.7. Based on this result and earlier published work on quasar luminosity functions at lower redshifts, it appears that there is a maximum in the comoving space density of quasars with M_{B}<-26 between redshifts 1.7 and 2.7.

Original language | English (US) |
---|---|

Pages (from-to) | 68-77 |

Number of pages | 10 |

Journal | Astronomical Journal |

Volume | 110 |

Issue number | 1 |

State | Published - Jul 1995 |

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### All Science Journal Classification (ASJC) codes

- Space and Planetary Science
- Astronomy and Astrophysics

### Cite this

*Astronomical Journal*,

*110*(1), 68-77.

}

*Astronomical Journal*, vol. 110, no. 1, pp. 68-77.

**Spectroscopic CCD surveys for quasars at large redshift. IV. Evolution of the luminosity function from quasars detected by their Lyman-alpha emission.** / Schmidt, Maarten; Schneider, Donald P.; Gunn, James E.

Research output: Contribution to journal › Article

TY - JOUR

T1 - Spectroscopic CCD surveys for quasars at large redshift. IV. Evolution of the luminosity function from quasars detected by their Lyman-alpha emission

AU - Schmidt, Maarten

AU - Schneider, Donald P.

AU - Gunn, James E.

PY - 1995/7

Y1 - 1995/7

N2 - We use 90 quasars detected by their Lyα emission to well-defined flux limits in the Palomar Transit Grism Survey to derive the luminosity function of quasars in the redshift range 2.75-4.75. Application of the V/Vmax test yields 〈Ve/Va〉=0.377±0.026, corresponding to a nonuniform distribution in comoving coordinates, such that the space density decreases with redshift. The luminosity function appears to be well represented by a power law with a slope corresponding to a factor of 5.6 per magnitude. We discuss and define the relationship between the line luminosity function and the continuum luminosity function of quasars. The space density for MB<-26 decreases by a factor of 2.7 per unit redshift beyond z=2.7. Based on this result and earlier published work on quasar luminosity functions at lower redshifts, it appears that there is a maximum in the comoving space density of quasars with MB<-26 between redshifts 1.7 and 2.7.

AB - We use 90 quasars detected by their Lyα emission to well-defined flux limits in the Palomar Transit Grism Survey to derive the luminosity function of quasars in the redshift range 2.75-4.75. Application of the V/Vmax test yields 〈Ve/Va〉=0.377±0.026, corresponding to a nonuniform distribution in comoving coordinates, such that the space density decreases with redshift. The luminosity function appears to be well represented by a power law with a slope corresponding to a factor of 5.6 per magnitude. We discuss and define the relationship between the line luminosity function and the continuum luminosity function of quasars. The space density for MB<-26 decreases by a factor of 2.7 per unit redshift beyond z=2.7. Based on this result and earlier published work on quasar luminosity functions at lower redshifts, it appears that there is a maximum in the comoving space density of quasars with MB<-26 between redshifts 1.7 and 2.7.

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M3 - Article

AN - SCOPUS:0038169542

VL - 110

SP - 68

EP - 77

JO - Astronomical Journal

JF - Astronomical Journal

SN - 0004-6256

IS - 1

ER -