Supernova Educator Guide Dr. Kevin McLin SSU E/PO Group 1 Monday, July 28, 2008

Supernova Educator

GuideDr. Kevin McLinSSU E/PO Group

1

Monday, July 28, 2008

Find the supernova

Image: R. Jay GeBany

Supernova light curves

From Reiss et al. 1998

Bri

gh

tne

ss

Supernovae brighten very quickly, then fade slowly (exponentially) over time

t=0 for these plots occurs at maximum light.

The actual explosion begins days before that, but it’s hard to catch.

Rare Look at a Supernova

XRT UVOT

Swift Images of NGC 2770

2008 January 7:00 UT

Rare Look at a Supernova

Swift Images of NGC 2770

XRT UVOT2008 January 9:00 UT

X-ray Light curve of SN2008DThis is the first supernova ever to be “caught in the act.”

Due to a serendipitous pointing of Swift to study SN2007uy in the galaxy NGC 2770.

It caught the “shock breakout,” where the shock from the core is breaking out of the star’s surface.missed by about one minute

Core of WR star collapses

Resulting shock disrupts envelope

Resulting shock disrupts envelope Star explodes

http://www.astro.princeton.edu/~alicia/SN2008D/

Additional Information

Three Supernova Activities

•Fishing for Supernovae•Crawl of the Crab•Magnetic Poles and Pulsars

Three Supernova Activities

•Fishing for Supernovae•Crawl of the Crab•Magnetic Poles and Pulsars

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Three Supernova Activities

•Fishing for Supernovae•Crawl of the Crab•Magnetic Poles and Pulsars

Crawl of the Crab

Crawl of the CrabWe will use two pictures of the Crab Nebula

1956

1999

Crab Pulsar

Lots of Knots

Measuring Expansion Gives Age

1.Assume pulsar remains at center of nebula

2.The knots move over time

3.Using both images we can measure the rate of expansion

4.Compare rate to size, we have the age

Measuring Expansion Gives Age1.Use spreadsheet provided

2.Enter x,y pairs for each knot in the two images

3.Plot rate vs. distance and determine the slope of the line ( =slope(y_data,x_data) )

4.The age is the reciprocal of the slope

So, let’s get started!