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SALT Science – UW Madison Properties of Quasar Host Galaxies Greg Mosby, Marsha Wolf, Christy Tremonti, and Eric Hooper The goal of this work is to understand connections between galaxies and the supermassive black holes at their centers, in the context of galaxy formation and evolution. We study this through the properties of luminous quasar host galaxies, objects in which the galaxy is actively feeding its black hole. This proposal focuses on a carefully selected sample of SDSS quasars, chosen over well-defined ranges of black hole mass, redshift and Eddington ratio in order to draw robust conclusions about these objects. SSPMODEL Above: Left: A schematic showing the observation setup and real data using SALT’s RSS. Right: An ideal pair of spectra that would be used as input to a stellar population modeling code developed by Mosby to determine host galaxy properties. Metallicities of GRB Host Galaxies Brian Morsony and John Chisholm University of Wisconsin-Madison Color composite image of the host galaxy of GRB060505, with GRB site shown (Thöne 2008) SALT spectra of GRB060505 taken on 5/11/13 with 1.14” seeing Accurately measuring mass outflow rates in starburst galaxies. Christy Tremonti, Corey&Wood 2013-1-UW-008 - Wood Tremonti Hubble Tarantula Treasury Project (HTTP) Mapping the Tarantula region with HST imaging PI Elena Sabbi (STScI) SALT RSS spectra map relationships between stars & gas, and yields insights into 3-D structures (NE region with strong line splitting & filaments shown above). Multiple slit positions to sample range of conditions. HST 30 Dor; Sabbi+ 2013, AJ, submitted 30 Doradus: Stellar Feedback: Nebular Motions & Ionization Jay Gallagher---Wisconsin Long slit RSS spectra sample gas kinematics & line ratios for comparison with HTTP HST study. Line splitting illustrates 3-D shell structure; strong [SII] signature of possible shocks. Hα [NII] HeI [SII] Time-Series Spectra of Accretion Flows in Pre-MS Binaries R. Mathieu & B. Tofflemire (UW-Madison) Initial SALT results – Hα Sept 2011 ϕ = 0.00 June 2012 ϕ ~0.21 High-resolution, time-series spectra will help constrain simulations of DQ Tau stars (see below) providing evidence for time-variable accretion flows onto PMS binaries from circumbinary material. Accretion Flows July 2012 Circumbinary Disk ϕ ~0.04 Å SALT is inherently ideal for time sensitive observing campaigns. The nightly frequency over months required for our science goals is within SALT’s capabilities but has yet to be achieved. Currently receiving high cadence observations! Circumstellar Disks Günther & Kley 2002, A&A 387, 550 • H F 8 6 1 5 2 K 1 0 G 0 5 9 4 3 K Optical companion: • • V=15.8 Strange spectrum SALT program: • Flux (arbit rary) • N a I M g I Like the “missing link” system PSR J1023 (Archibald et al. 2009) that went from MSP ⬌X-ray binary H Radio timing shows weird variations: lots of gas floating around the system F e I • Pulsar C a I • Eclipsing millisecond pulsar discovered by Parkes (binary period=15h) C a II • PSR J1723 G 5 5 4 9 5 K RSS spectra to measure orbit G 8 5 2 4 8 K 6 K 0 5 0 4 7 K K 1 4 9 5 5 K 4 K 2 4 8 5 3 K 2 p u ls a r 0 Crawford et al. (2013, ApJ, G 2 5 7 9 4 K 8 4 0 0 0 4 5 0 0 5 0 0 0 5 5 0 0 Wavelengt h ( Å) 6 0 0 0 6 5 0 0 7 0 0 0 In this program (Orio et al.) we monitor recent novae, supersoft X-ray sources and UV transients to study the accretion process in close binaries through the emission lines diagnostics. These line profiles were observed for the recurrent nova T Pyx a year and a half after the outburst. Nebular [O III] lines at 5007 Å were still very strong and confirmed a bipolar mass ejection. There seem to be two distincts region of emission, both asymmetric. The He II emission line at 4686 Å, much less intense, has a double peak profile with the blue (receding part) less strong than the red like the [O III], but seems to be emitted in a different region. Megaflares on Tiny Stars Change in flux at 3500Å “big” flare “small” flare M-dwarf star (YZ CMi); major flare caught in Jan 2012. Star 100x brighter in U-band. SALT spectra taken at vertical grey lines. • Major source of variability for time-domain astronomy surveys. Especially LSST. • Large impact on habitability of low-mass stars. (obs Jan 2012, spectra: Brown et al. SALT/RSS; photometry: Kowalski et al. WHT/La Palma) 12 Spectral Movie of Megaflare Peak flare emission Counts/second 100 pre-flare spectrum 10 1 3000Å 3500Å Wavelength M-dwarf star, 15 sec cadence, R~1000, 70x faster than VLT! 4500Å 5500Å http://www.astro.wisc.edu/~bpbrown/Movies/ (Brown et al.; obs Jan 2012, SALT/RSS) Hydrogen (and other) emission lines at peak Megaflares on tiny stars Signature of hot Black body? Comparable energy release to large (X-class) solar flare. Whole star brightens by ~100x. Program has continued through 2013, strong undergrad involvement.