-- AnishaVadher - 29 Oct 2016

To do list:

  • Anisha:
  • Aaron:
    • Simulate a star field using known star parameters.
  • Laura:
    • Check star finder finds all stars in images from observation.
Progress:

Observation 1: Looked at M103, Dragonfly Cluster and Double Cluster with luminescence, red, green (visual) and blue filters all at -15 degrees.

Anisha:

  • Used Simbad catalog in Aladin to get RA/DEC and B, V and R magnitudes to give to Aaron to a real simulate starfield
  • Used data to plot B-V HR diagram for observed clusters
  • Hertzsprung Russell diagram for double cluster using data from Simbad:
    HRDoubleCluster.png
  • Hertzsprung Russell diagram for M103 using data from Simbad:
    HRM103.png
Aaron:

Simulation program: Simulation_test7.py.txt

  • Given list of star parameters fom Anisha - includes positions (RA, DEC) and magnitudes (for B, V, R filters).
  • Method for converting angular coordinates to pixel coordinates:
    • Take camera/telescope alignment as coordinates for image center, or origin.
    • Take difference in star coordinates and origin coordinates (e.g. RA_star-RA_o) to gain angular positions in relation to origin.
    • Use plate scale (e.g 0.61 arcsec/pixel) to convert angular position to pixel scale position. (Not entirely accurate - isn't linear near image edges)
    • Linear transformation of positions so origin is in bottom-left corner of image.
  • Tested generation for recorded stars in Double Cluster and M103. For both: 1530x1020 pixels, Sigma_x=Sigma_y=3, rho=0, includes background+saturation
  • M103 (center RA/DEC (J2000): 1h33m12.01s/+60deg42'00.0"):
  • M103Test1.png
  • Double Cluster (center RA/DEC (J2000): 2h19m0.00s/+57deg09'00.0") - generated with switched axes due to programming error:
  • DoubleClusterTest1.png
Laura:
  • Algorithm can return:
    • The number of stars in the image
    • The number of pixels in each star
    • The coordinates of the pixels in the stars
    • The pixel values at each coordinate
    • The weighted average of x and y positions
  • Next step is to convert coordinates to RA and Dec and compare to actual values
  • Luminescence image of Double Cluster at 15s exposure:
DBCL_Lum_15s_FitsImage.png
  • Stars located using algorithm, counted 279 stars:
DBLC_Lum_15s_StarFinder.png
Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng BeehiveClusterTest1.png r1 manage 9.1 K 02 Nov 2016 - 14:49 AaronAndrews Beehive Cluster simulation 1 (size=1530x1020, exposure=10 secs, saturated, no background)
PNGpng DBCL_Lum_15s_FitsImage.png r1 manage 144.1 K 04 Nov 2016 - 10:37 LauraBevilacqua  
PNGpng DBLC_Lum_15s_StarFinder.png r1 manage 31.0 K 04 Nov 2016 - 10:37 LauraBevilacqua  
PNGpng DoubleClusterTest1.png r1 manage 12.3 K 04 Nov 2016 - 12:37 AaronAndrews Double Cluster simulation - axes switched
JPEGjpg Double_Cluster.jpg r1 manage 135.8 K 04 Nov 2016 - 13:07 AnishaVadher Double cluster on Aladin
PNGpng HRDoubleCluster.png r1 manage 115.9 K 04 Nov 2016 - 11:33 AnishaVadher Hertzsprung Russell diagram for double cluster using data from Simbad
PNGpng HRM103.png r1 manage 37.2 K 04 Nov 2016 - 13:04 AnishaVadher Hertzsprung Russell diagram for M103 using data from Simbad
JPEGjpg M103.jpg r1 manage 118.2 K 04 Nov 2016 - 13:08 AnishaVadher M103 on Aladin
PNGpng M103Test1.png r1 manage 16.3 K 04 Nov 2016 - 12:40 AaronAndrews M103 simulation
Texttxt Simulation_test7.py.txt r1 manage 15.7 K 02 Nov 2016 - 15:58 AaronAndrews Simulation test 7 (02/11/2016)
Edit | Attach | Watch | Print version | History: r9 < r8 < r7 < r6 < r5 | Backlinks | Raw View | Raw edit | More topic actions

Physics WebpagesRHUL WebpagesCampus Connect • Royal Holloway, University of London, Egham, Surrey TW20 0EX; Tel/Fax +44 (0)1784 434455/437520

Topic revision: r9 - 04 Nov 2016 - AaronAndrews

 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright © 2008-2021 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding RHUL Physics Department TWiki? Send feedback