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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"

24808 results found.

  1. GRB000801, VLT-Antu R-band observations
  2. GRB 991208 Host Galaxy Imaging
  3. IPN localization of GRB000730B
  4. GRB 990510: Possible detection of a host galaxy
  5. GRB 990510 Host Galaxy Discovery
  6. IPN localization of GRB000727
  7. GRB 990712: Late time HST/STIS Observations
  8. GRB 991216, HST/STIS observations
  9. GRB000620, Radio Observations
  10. GRB000630, optical observations
  11. GRB000630, Revised BVRI Field Photometry
  12. GRB000630, Optical Observations
  13. GRB000630, optical observations
  14. GRB000630, optical observations
  15. GRB000630, BVRI Field Photometry
  16. GRB000630, optical observations
  17. GRB000630: Optical observations
  18. GRB000630, Radio Observations
  19. possible optical counterpart of GRB 000630
  20. GRB 000620, optical observations
  21. GRB000418, HST/STIS Observations
  22. GRB990123: Late-time HST/STIS observations of the host
  23. GRB000620, optical observations
  24. GRB000615: H-band observations
  25. GRB990308, HST/STIS observations of the host galaxy
  26. GRB000620 - Optical observations
  27. GRB000620 Optical observations
  28. GRB000620: BeppoSAX WFC and GRBM detection
  29. GRB000607, optical observations
  30. GRB 000615: NIR further observations
  31. GRB990123, HST/STIS observations of the host galaxy
  32. GRB000616 optical observations
  33. GRB 000615, near-infrared observations
  34. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  35. GRB000615, further R-band photometry
  36. GRB 000615: NIR observations
  37. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  38. GRB000615, R-band photometry
  39. The Hosts of GRB 980703 and GRB 971214
  40. GRB 000301C: Further Late-Time HST/STIS observations
  41. GRB000528: follow-up X-ray measurements and update of IPN annulus
  42. GRB980519, HST/STIS observations of the host galaxy
  43. GRB000604 optical non-detection
  44. GRB000604 - Optical observations
  45. GRB000604, optical observations
  46. GRB000528, optical observations at ESO
  47. GRB 000604 optical observations
  48. GRB 000418: Detection of the Host Galaxy
  49. GRB000604, optical observations, comparison with DPOSS
  50. GRB000528, Radio Observations
  51. X-ray Afterglow of GRB 000529
  52. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  53. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  54. GRB 000528 - WFC measurements
  55. GRB000519, BVRI field photometry
  56. IPN triangulation of GRB000519
  57. GRB000508B, optical photometry
  58. GRB000508B, BVR field photometry
  59. Possible GRB-related phenomenon
  60. RXTE/ASM and IPN localization of GRB 000508B
  61. GRB000424, UBVRI field photometry
  62. GRB000418, UBVRI field photometry update
  63. GRB000424, optical observations
  64. GRB 000429, optical observation
  65. GRB 000429, UBVRI field photometry
  66. GRB 000418, UBVRI field photometry
  67. GRB 000418, optical observation
  68. GRB 000418, Optical Observation
  69. GRB000418, near-infrared observations
  70. Correction to IPN error box for GRB000419
  71. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  72. GRB000416 BRJK observations
  73. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  74. GRB 000408, optical observations
  75. GRB 991208, UBVRI field photometry
  76. GRB000408, lotis optical observations
  77. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  78. GRB000301C - Addendum to GCN 623
  79. GRB 000323, optical observations
  80. GRB 000326: Optical Observations
  81. GRB000326, Radio observations
  82. GRB000313, Radio observations
  83. GRB 000313 - optical transient in the BATSE error box
  84. GRB 000307, Optical Observations
  85. GRB 000307, BVRI Field Photometry
  86. GRB 000301C: A Precise Redshift Determination
  87. GRB 000301C, Optical Observation
  88. GRB 000301C: HST/STIS CCD Imaging of the field
  89. IPN error box for GRB000307
  90. GRB000301C, optical R-band observations
  91. GRB 000301C Optical Observations
  92. GRB 000301C: K' Observations
  93. GRB000301C OT candidate optical observations
  94. GRB000301C - Host galaxy not detected in R (?)
  95. Optical observations of GRB000301c
  96. GRB000301C, Radio observations
  97. GRB000301C, Radio observations
  98. GRB000301C, near-infrared observations (JHK' imaging)
  99. GRB 000301c near-IR observations
  100. GRB 000301C, UBVRI field photometry

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