Observations with the Hubble Space Telescope (HST), conducted since 1990, now
offer an unprecedented glimpse into fast astrophysical shocks in the young
remnant of supernova 1987A. Comparing observations taken in 2010 using the
refurbished instruments on HST with data taken in 2004, just before the Space
Telescope Imaging Spectrograph failed, we find that the Ly-a and H-a lines from
shock emission continue to brighten, while their maximum velocities continue to
decrease. We observe broad blueshifted Ly-a, which we attribute to resonant
scattering of photons emitted from hotspots on the equatorial ring. We also
detect NV~\lambda\lambda 1239,1243 A line emission, but only to the red of
Ly-A. The profiles of the NV lines differ markedly from that of H-a, suggesting
that the N^{4+} ions are scattered and accelerated by turbulent electromagnetic
fields that isotropize the ions in the collisionless shock.Comment: Science, accepted. Science Express, 02 Sept 2010. 5 figures.
  Supporting online material can be found at
  http://www.sciencemag.org/cgi/content/full/sci;science.1192134/DC

A. Crotts

Arnett

C. Fransson

C. S. J. Pun

E. Dwek

G. Sonneborn

J. C. Wheeler

J. Larsson

J. Sollerman

J. T. Stocke

K. France

K. Heng

L. Wang

McCray

Morris

N. Panagia

N. Smith

P. Bouchet

P. Challis

P. Lundqvist

P. M. Garnavich

R. McCray

R. P. Kirshner

S. S. Lawrence

Science

English

arXiv

The young remnant of supernova 1987A (SN 1987A) offers an unprecedented glimpse into the hydrodynamics and kinetics of fast astrophysical shocks. We have been monitoring SN 1987A with the Hubble Space Telescope (HST) since it was launched. The recent repair of the Space Telescope Imaging Spectrograph (STIS) allows us to compare observations in 2004, just before its demise, with those in 2010, shortly after its resuscitation by NASA astronauts. We find that the Ly-alpha and H-alpha lines from shock emission continue to brighten, while their maximum velocities continue to decrease. We report evidence for nearly coherent, resonant scattering of Lya photons (to blueshifts approximately -12,000 km /s) from hotspots on the equatorial ring. We also report emission to the red of Ly-alpha that we attribute to N v lambda lambda 1239,1243 Angstrom line emission. These lines are detectable because, unlike hydrogen atoms, N4+ ions emit hundreds of photons before they are ionized. The profiles of the N v lines differ markedly from that of H-alpha. We attribute this to scattering of N4+ ions by magnetic fields in the ionized plasma. Thus, N v emission provides a unique probe of the isotropization zone of the collisionless shock. Observations with the recently installed Cosmic Origins Spectrograph (COS) will enable us to observe the N v lambda lambda 1239,1243 Angstrom line profiles with much higher signal-to-noise ratios than possible with STIS and may reveal lines of other highly ionized species (such as C IVlambda lambda 1548,1551 Angstrom) that will test our explanation for the N v emissio

Pun, Chun S. J.

Lundqvist, Peter

Dwek, Eli

Stocke, John T.

Panagia, Nino

McCray, Richard

Larsson, Josefin

Heng, Kevin

Kirshner, Robert P.

Bouchet, Patrice

Garnavich, Peter M.

Smith, Nathan

Fransson, Claes

Challis, Peter

Wheeler, J. Craig

Sonneborn, George

Crotts, Arlin

Sollerman, Jesper

France, Kevin

NASA Technical Reports Server

Observing Supernova 1987A with the Refurbished Hubble Space Telescope

International audienceObservations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 using the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Lyα and Hα lines from shock emission continue to brighten, while their maximum velocities continue to decrease. We observe broad blueshifted Lyα, which we attribute to resonant scattering of photons emitted from hotspots on the equatorial ring. We also detect N v λλ1239,1243 Å line emission, but only to the red of Lyα. The profiles of the N v lines differ markedly from that of Hα, suggesting that the N4+ ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock

Mccray, Richard

P. Kirshner, Robert

M. Garnavich, Peter

S. Lawrence, Stephen

S. J. Pun, Chun

T. Stocke, John

Wang, Lifan

Craig Wheeler, J.

HAL: Hyper Article en Ligne

Observing supernova 1987A with the refurbished Hubble space telescope

Observations with the Hubble Space Telescope (HST), conducted since 1990, now offer an unprecedented glimpse into fast astrophysical shocks in the young remnant of supernova 1987A. Comparing observations taken in 2010 with the use of the refurbished instruments on HST with data taken in 2004, just before the Space Telescope Imaging Spectrograph failed, we find that the Lyα and Hα lines from shock emission continue to brighten, whereas their maximum velocities continue to decrease. We observe broad, blueshifted Lyα, which we attribute to resonant scattering of photons emitted from hot spots on the equatorial ring. We also detect N v λλ1239, 1243 angstrom line emission, but only to the red of Lyα. The profiles of the N v lines differ markedly from that of Hα, suggesting that the N 4+ ions are scattered and accelerated by turbulent electromagnetic fields that isotropize the ions in the collisionless shock.postprin

France, K

McCray, R

Heng, K

Kirshner, RP

Challis, P

Bouchet, P

Crotts, A

Dwek, E

Fransson, C

Garnavich, PM

Larsson, J

Lawrence, SS

Lundqvist, P

Panagia, N

Pun, CSJ

Smith, N

Sollerman, J

Sonneborn, G

Stocke, JT

Wang, L

Wheeler, JC

HKU Scholars Hub

Observing supernova 1987A with the refurbished hubble space telescope

HAL Portal UBS (Université Bretagne Sud)

HAL-CEA

Let Me See Your Supernova
          
            As the matter expelled from a supernova travels through and interacts with the interstellar medium, it creates a radiating structure called a supernova remnant. In 1987, astronomers detected a bright supernova in our galaxy, SN 1987A, the remains of which are now expanding into and interacting with a dense ring of gas and dust that surrounds the explosion site.
            
              France
              et al.
            
            (p.
            1624
            , published online 2 September; see the Perspective by
            
              Laming
            
            ) obtained spectroscopic data of the ring surrounding SN 1987A and compared it with similar data acquired in 2004. Because SN 1987A is so close to us, the explosion was visible to the naked eye and the results provide a glimpse into the hydro dynamics and kinetics of fast astrophysical shocks in a young supernova remnant.
          </jats:p

Observing Supernova 1987A with the Refurbished Hubble Space Telescope

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