Louis-Benoit Desroches

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We analyze the fundamental plane projections of elliptical galaxies as a function of lumi-nosity, using a sample of ≈ 80, 000 galaxies drawn from Data Release 4 (DR4) of the Sloan Digital Sky Survey (SDSS). We exclude brightest cluster galaxies (BCGs) from our sample because of a problem with the default pipeline sky subtraction for BCGs. The observables we(More)
The molecular basis for changes in cytokine expression during T helper (Th) cell subset differentiation is not well understood. We have characterized transcriptional events related to cytokine gene expression in populations of naive T cell receptor-transgenic T cells as they are driven in vitro toward Th1 or Th2 phenotypes by interleukin (IL)-12 or IL-4(More)
We present optical observations of the low-luminosity Seyfert 1 nucleus of NGC 4395, as part of a multiwavelength reverberation-mapping program. Observations were carried out over two nights in 2004 April at Lick, Wise, and Kitt Peak Observatories. We obtained V-band and B-band photometry, and spectra over the range 3500–6800Å. Simultaneous Hubble Space(More)
We report on two Chandra observations, and a simultaneous Hubble Space Telescope ultraviolet observation, of the dwarf Seyfert 1 galaxy NGC 4395. Each Chandra observation had a duration of ∼30 ks, with a separation of ∼50 ks. The spectrum was observed to harden between these observations via a scaling down of the soft-band flux. The inter-observation(More)
While both society and astronomy have evolved greatly over the past fifty years, the academic institutions and incentives that shape our field have remained largely stagnant. As a result, the astronomical community is faced with several major challenges, including: (1) the training that we provide does not align with the skills that future astronomers will(More)
A reverberation-mapping program on NGC 4395, the least-luminous known Seyfert 1 galaxy, undertaken with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, yields a measurement of the mass of the central black hole M BH = (3.6±1.1)×10 5 M ⊙. The observations consist of two visits of 5 orbits each, in 2004 April and July. During each of(More)
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