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)
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)
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)
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