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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"

25571 results found.

  1. Chandra Position of GRB000210
  2. IPN triangulation of GRB000830
  3. HST/STIS observations of the host galaxy of GRB 980329
  4. IPN localization of GRB000820
  5. GRB000812, TNG R-band observations
  6. GRB000801 & GRB000730, Gamma Ray Observations
  7. GRB000730, Gamma Ray Observations
  8. IPN localization of GRB000812
  9. IPN localization of GRB000811
  10. GRB000801, Gamma Ray Observations
  11. GRB000301C, UBVI optical observations
  12. IPN localization of GRB000801
  13. IPN localization of GRB000730B
  14. IPN localization of GRB000730
  15. GRB 990510: Possible detection of a host galaxy
  16. IPN localization of GRB000727
  17. GRB 990712: Late time HST/STIS Observations
  18. GRB 991216, HST/STIS observations
  19. GRB981226, HST/STIS observations of the host galaxy
  20. GRB000630, optical observations
  21. GRB000630, Optical Observations
  22. GRB000630, optical observations
  23. GRB000630, optical observations
  24. GRB000630: Optical observations
  25. GRB000630, Radio Observations
  26. IPN triangulation of GRB000630
  27. GRB000418, HST/STIS Observations
  28. GRB 990506, HST/STIS Observations of the Host Galaxy
  29. GRB000623
  30. GRB000615: H-band observations
  31. IPN annulus for GRB000620
  32. GRB 000615: NIR further observations
  33. BeppoSAX ALERT: GRB000620
  34. GRB000620: BeppoSAX Alert
  35. GRB990123, HST/STIS observations of the host galaxy
  36. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  37. GRB000616 [IPN Position]
  38. GRB000615B [IPN Position]
  39. GRB000615, further R-band photometry
  40. GRB000615, R-band photometry
  41. GRB000615: BeppoSAX GRB Alert
  42. The Hosts of GRB 980703 and GRB 971214
  43. GRB 000301C: Further Late-Time HST/STIS observations
  44. GRB980519, HST/STIS observations of the host galaxy
  45. GRB000607, Radio Observations
  46. BeppoSAX X-ray transient/possible GRB000608
  47. GRB000604 - Optical observations
  48. GRB000607, A SHORT, HARD BURST
  49. GRB000604, optical observations
  50. GRB000604, optical observations, comparison with DPOSS
  51. GRB000604 [IPN Position]
  52. GRB000528, Radio Observations
  53. X-ray Afterglow of GRB 000529
  54. IPN localization and time history of GRB000528
  55. New IPN localization of GRB000529
  56. GRB000519: Optical observations
  57. GRB 000528 - WFC measurements
  58. GRB000529: BeppoSAX WFC position
  59. GRB 000528 Optical Observations
  60. IPN triangulation of GRB000519
  61. IPN triangulation of GRB000516
  62. Re: GRB000508B : Optical observations
  63. GRB 000418, Optical observation
  64. Possible GRB-related phenomenon
  65. RXTE/ASM and IPN localization of GRB 000508B
  66. GRB000424, optical observations
  67. IPN localization of GRB000429
  68. GRB000418, Radio detection
  69. GRB 000418, optical observation
  70. GRB 000418, Optical Observation
  71. GRB000418, near-infrared observations
  72. Correction to IPN error box for GRB000419
  73. IPN error box for GRB000418
  74. GRB000419 [IPN Position]
  75. 1SAXJ1715.0-7134 refined position
  76. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  77. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  78. Budget cuts in BeppoSAX operations: impact on GRB observations
  79. GRB000301c results
  80. GRB000408: Optical CCD Observations from MIRO
  81. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  82. GRB000408 [IPN Position]
  83. GRB000326 Optical Observations
  84. GRB 000326: Optical Observations
  85. GRB 000307 optical observations
  86. GRB000323 [IPN Position]
  87. GRB000313, Radio observations
  88. GRB000301C - B and R photometry
  89. GRB000301C - R photometry
  90. GRB 000307, Optical Observations
  91. GRB 000301C: Optical Spectrum and Redshift
  92. GRB 000301C: Optical Spectrum and Redshift
  93. GRB 000301C: A Precise Redshift Determination
  94. GRB 000301C, Optical Observation
  95. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  96. GRB 000301C: HST/STIS CCD Imaging of the field
  97. IPN error box for GRB000307
  98. GRB 000301c: K' observations
  99. GRB000301C, optical R-band observations
  100. GRB000301c - R photometry and nearby faint source confirmation

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