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Silbermann, N.

Publications and source records attributed to Silbermann, N..

14 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2000

The mid-infrared spectra of normal galaxies

The mid-infrared spectra (2.5-5 and 5.7-11.6 mu m) obtained by ISOPHOT reveal the interstellar medium emission from galaxies powered by star formation to be strongly dominated by the aromatic features at 6.2, 7.7, 8.6, and 11.3 mu m. Additional emission appears in between the features, and an underlying continuum is clearly evident at 3-5 mu m. This continuum would contribute about a third of the luminosity in the 3-13 mu m range. The features together carry 5%-30% of the 40-120 mu m. range.FIR) luminosity.

Mid-infrared spectra spectrophotometry↗
NASA NTRS1999

A Cepheid Distance to NGC 4603 in the Centaurus Cluster

In an attempt to use Cepheid variables to determine the distance to the Centaurus cluster, we have obtained images of NGC 4603 with the Hubble Space Telescope for 9 epochs (totalling 24 orbits) over 14 months in the F555W filter and 2 epochs (totalling 6 orbits) in the F814W filter.

Cepheids distance redshifs large scale structure o↗
NASA NTRS1996

The Hubble Space Telescope Extragalactic Distance Scale Key Project. X. The Cepheid Distance to NGC 7331

The distance to NGC 7331 has been derived from Cepheid variables observed with HST/WFPC2, as part of the Extragalactic Distance Scale Key Project. Multi-epoch exposures in F555W(~V) and F814W (~1), with photometry derived independently from DoPHOT and DAOPHOT/ALLFRAME programs, which were used to detect a total of 14 reliable Cepheids, with periods between 11 and 42 days.

Cepheids galaxies distances redshifts NGC 7331 ear↗