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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"

35946 results found.

  1. J and K band observations of GRB 000926
  2. GRB 000926: Lightcurve Update and Predictions
  3. GRB 000926, optical observation by Oksanen (vsnet-grb)
  4. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  5. CONCAM crude optical limits before and after GRB000926
  6. GRB 000926: Preliminary R-band Lightcurve
  7. GRB 000926 HST/Chandra TOO Status
  8. Spectroscopic Redshift of GRB 000926
  9. GRB 000926, Optical Observation
  10. GRB 000926: Optical candidate
  11. Optical candidate for GRB000926
  12. IPN triangulation of GRB000926
  13. GRB 000911, BVRI field photometry
  14. GRB000911: Sub-millimeter observations
  15. IPN triangulation of GRB000925
  16. IPN triangulation of GRB000911
  17. IPN triangulation of GRB000910
  18. False GRB alarm from RXTE/ASM on 8 Sept 2000
  19. GRB 000830: Optical observations
  20. GRB000830: Optical observations
  21. GRB000830, TNG B-band observations
  22. GRB000830, BVRI field photometry
  23. GRB000830: Optical observations
  24. GRB000210, Optical observations
  25. Chandra Position of GRB000210
  26. "Snapshot" afterglow IDs and GRB 000830
  27. IPN triangulation of GRB000830
  28. HST/STIS observations of the host galaxy of GRB 980329
  29. HST/STIS observations of the chaotic environment of GRB 980613
  30. IPN localization of GRB000820
  31. GRB000801 & GRB000730, Gamma Ray Observations
  32. GRB000730, Gamma Ray Observations
  33. GRB000812, Radio observations
  34. IPN localization of GRB000812
  35. IPN localization of GRB000811
  36. GRB000801, Gamma Ray Observations
  37. GRB000801, VLT-Antu R-band observations
  38. GRB 991208 Host Galaxy Imaging
  39. Updated IPN coordinates for GRB000801
  40. IPN localization of GRB000801
  41. IPN localization of GRB000730B
  42. IPN localization of GRB000730B
  43. IPN localization of GRB000730
  44. GRB 990510: Possible detection of a host galaxy
  45. GRB 990510 Host Galaxy Discovery
  46. GRB 000727, optical observations
  47. IPN localization of GRB000727
  48. GRB 990705, HST/STIS observations of the host galaxy
  49. GRB 990712: Late time HST/STIS Observations
  50. GRB 991216, HST/STIS observations
  51. GRB981226, HST/STIS observations of the host galaxy
  52. GRB 000630: Detection of the Optical Afterglow
  53. GRB000630, Revised BVRI Field Photometry
  54. GRB000630, Optical Observations
  55. GRB000630, optical observations
  56. GRB000630, BVRI Field Photometry
  57. GRB000630, optical observations
  58. GRB000630: Optical observations
  59. possible optical counterpart of GRB 000630
  60. IPN triangulation of GRB000630
  61. GRB 000623, optical observations
  62. GRB 000620, optical observations
  63. GRB000418, HST/STIS Observations
  64. GRB990123: Late-time HST/STIS observations of the host
  65. GRB 990506, HST/STIS Observations of the Host Galaxy
  66. GRB000623
  67. GRB 000620: J-band observations
  68. GRB990308, HST/STIS observations of the host galaxy
  69. IPN annulus for GRB000620
  70. GRB000615, Radio observations
  71. GRB000607, optical observations
  72. GRB 000615: NIR further observations
  73. BeppoSAX ALERT: GRB000620
  74. GRB000620: BeppoSAX Alert
  75. GRB990123, HST/STIS observations of the host galaxy
  76. GRB 000615, near-infrared observations
  77. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  78. GRB000616 [IPN Position]
  79. GRB000615B [IPN Position]
  80. GRB000615, further R-band photometry
  81. GRB 000615: NIR observations
  82. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  83. GRB000615, R-band photometry
  84. GRB980425, HST/STIS observations of the host galaxy
  85. GRB000615: BeppoSAX GRB Alert
  86. The Hosts of GRB 980703 and GRB 971214
  87. GRB 000301C: Further Late-Time HST/STIS observations
  88. GRB000528: follow-up X-ray measurements and update of IPN annulus
  89. GRB980519, HST/STIS observations of the host galaxy
  90. GRB000607, Radio Observations
  91. GRB000604 - Optical observations
  92. GRB000607, A SHORT, HARD BURST
  93. GRB000604, optical observations
  94. GRB000528, optical observations at ESO
  95. GRB 000604 optical observations
  96. GRB 000418: Detection of the Host Galaxy
  97. GRB000604, optical observations, comparison with DPOSS
  98. GRB000604 [IPN Position]
  99. X-ray Afterglow of GRB 000529
  100. GRB000529: BeppoSAX NFI follow-up preliminary analysis

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