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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

37048 results found.

  1. GRB000926 - Optical observations
  2. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  3. J and K band observations of GRB 000926
  4. GRB 000926: Lightcurve Update and Predictions
  5. GRB 000926, optical observation by Oksanen (vsnet-grb)
  6. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  7. CONCAM crude optical limits before and after GRB000926
  8. GRB 000926: Preliminary R-band Lightcurve
  9. GRB 000926 HST/Chandra TOO Status
  10. Spectroscopic Redshift of GRB 000926
  11. GRB 000926, Optical Observation
  12. GRB 000926: Optical candidate
  13. Optical candidate for GRB000926
  14. IPN triangulation of GRB000926
  15. GRB 000911, BVRI field photometry
  16. GRB000911: Sub-millimeter observations
  17. IPN triangulation of GRB000925
  18. IPN triangulation of GRB000911
  19. IPN triangulation of GRB000910
  20. False GRB alarm from RXTE/ASM on 8 Sept 2000
  21. GRB 000830: Optical observations
  22. GRB000830: Optical observations
  23. GRB000830, TNG B-band observations
  24. GRB000830, BVRI field photometry
  25. GRB000830: Optical observations
  26. GRB000210, Optical observations
  27. Chandra Position of GRB000210
  28. "Snapshot" afterglow IDs and GRB 000830
  29. IPN triangulation of GRB000830
  30. HST/STIS observations of the host galaxy of GRB 980329
  31. HST/STIS observations of the chaotic environment of GRB 980613
  32. IPN localization of GRB000820
  33. GRB000801 & GRB000730, Gamma Ray Observations
  34. GRB000730, Gamma Ray Observations
  35. GRB000812, Radio observations
  36. IPN localization of GRB000812
  37. IPN localization of GRB000811
  38. GRB000801, Gamma Ray Observations
  39. GRB000801, VLT-Antu R-band observations
  40. GRB 991208 Host Galaxy Imaging
  41. Updated IPN coordinates for GRB000801
  42. IPN localization of GRB000801
  43. IPN localization of GRB000730B
  44. IPN localization of GRB000730B
  45. IPN localization of GRB000730
  46. GRB 990510: Possible detection of a host galaxy
  47. GRB 990510 Host Galaxy Discovery
  48. GRB 000727, optical observations
  49. IPN localization of GRB000727
  50. GRB 990705, HST/STIS observations of the host galaxy
  51. GRB 990712: Late time HST/STIS Observations
  52. GRB 991216, HST/STIS observations
  53. GRB981226, HST/STIS observations of the host galaxy
  54. GRB 000630: Detection of the Optical Afterglow
  55. GRB000630, Revised BVRI Field Photometry
  56. GRB000630, Optical Observations
  57. GRB000630, optical observations
  58. GRB000630, BVRI Field Photometry
  59. GRB000630, optical observations
  60. GRB000630: Optical observations
  61. possible optical counterpart of GRB 000630
  62. IPN triangulation of GRB000630
  63. GRB 000623, optical observations
  64. GRB 000620, optical observations
  65. GRB000418, HST/STIS Observations
  66. GRB990123: Late-time HST/STIS observations of the host
  67. GRB 990506, HST/STIS Observations of the Host Galaxy
  68. GRB000623
  69. GRB 000620: J-band observations
  70. GRB990308, HST/STIS observations of the host galaxy
  71. IPN annulus for GRB000620
  72. GRB000615, Radio observations
  73. GRB000607, optical observations
  74. GRB 000615: NIR further observations
  75. BeppoSAX ALERT: GRB000620
  76. GRB000620: BeppoSAX Alert
  77. GRB990123, HST/STIS observations of the host galaxy
  78. GRB 000615, near-infrared observations
  79. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  80. GRB000616 [IPN Position]
  81. GRB000615B [IPN Position]
  82. GRB000615, further R-band photometry
  83. GRB 000615: NIR observations
  84. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  85. GRB000615, R-band photometry
  86. GRB980425, HST/STIS observations of the host galaxy
  87. GRB000615: BeppoSAX GRB Alert
  88. The Hosts of GRB 980703 and GRB 971214
  89. GRB 000301C: Further Late-Time HST/STIS observations
  90. GRB000528: follow-up X-ray measurements and update of IPN annulus
  91. GRB980519, HST/STIS observations of the host galaxy
  92. GRB000607, Radio Observations
  93. GRB000604 - Optical observations
  94. GRB000607, A SHORT, HARD BURST
  95. GRB000604, optical observations
  96. GRB000528, optical observations at ESO
  97. GRB 000604 optical observations
  98. GRB 000418: Detection of the Host Galaxy
  99. GRB000604, optical observations, comparison with DPOSS
  100. GRB000604 [IPN Position]

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