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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"

26042 results found.

  1. GRB 991208 Host Galaxy Imaging
  2. GRB 991216, HST/STIS observations
  3. GRB000620, Radio Observations
  4. GRB981226, HST/STIS observations of the host galaxy
  5. GRB000630, optical observations
  6. GRB 000630: Detection of the Optical Afterglow
  7. GRB000630, BVRI Field Photometry
  8. GRB 990506, HST/STIS Observations of the Host Galaxy
  9. GRB990308, HST/STIS observations of the host galaxy
  10. GRB990123, HST/STIS observations of the host galaxy
  11. GRB000615, further R-band photometry
  12. GRB000528: follow-up X-ray measurements and update of IPN annulus
  13. Optical Follow-up of GRB000529 Error Box
  14. X-ray Afterglow of GRB 000529
  15. GRB000519, BVRI field photometry
  16. GRB 000418, Optical observation
  17. GRB000508B, BVR field photometry
  18. Possible GRB-related phenomenon
  19. GRB000424, UBVRI field photometry
  20. GRB 000429, UBVRI field photometry
  21. GRB000418, K'-band photometry
  22. GRB 000418, Optical Observation
  23. GRB 000418, optical observation
  24. GRB 000418, Optical Observation
  25. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  26. Budget cuts in BeppoSAX operations: impact on GRB observations
  27. GRB000408: Optical CCD Observations from MIRO
  28. GRB000326 Optical Observations
  29. GRB 000313 - optical transient in the BATSE error box
  30. GRB 000301C: K' Observations
  31. GRB 000301c near-IR observations
  32. GRB 000301C, Optical Color
  33. GRB000301C 250 GHz detection
  34. GRB000301C, near-infrared observations (JHK' photometry)
  35. GRB000301C, optical observations
  36. GRB000301c, near-infrared observations
  37. GRB 000214 near-IR observations
  38. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  39. GRB000210, Radio Observations
  40. GRB000210 X-ray afterglow
  41. GRB000214: X-ray afterglow candidate
  42. Correction to Chandra Position of GRB000210 afterglow
  43. Chandra Observations of GRB000210 X-ray Afterglow
  44. GRB000210: possible afterglow detection with BeppoSAX NFI
  45. GRB 991208, radio observations
  46. GRB 000115 Optical observations
  47. BATSE Observations of GRB000115
  48. Second RXTE Observation of GRB 000115
  49. GRB991216 late optical observation
  50. GRB 991216 VLBA Observations
  51. GRB 991216: J band spectrophotometry
  52. GRB 991216 RXTE ASM Observations
  53. Chandra observation of the X-ray afterglow of GRB991216
  54. GRB991216 Optical and IR observations
  55. GRB991216 radio observations
  56. GRB991216 Optical and infrared observations of Beethoven Burst
  57. GRB 991216 Radio Observations
  58. GRB 991208 Infrared Detection
  59. GRB 991216--Summary of RXTE Observations
  60. GRB 991216, Optical Afterglow
  61. GRB991216 Optical Observations
  62. R-band Observations of GRB991208 at TNG
  63. GRB 991208 Keck Spectroscopy
  64. GRB991208 - millimeter detection
  65. GRB 991208, Optical Observation
  66. GRB991208, optical observations
  67. GRB 991208 - OVRO detection
  68. GRB 991208 Optical Decay
  69. GRB 991208 optical observations
  70. GRB 991208 optical observations
  71. GRB 991208: Radio Observations
  72. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  73. GRB 991014 - BeppoSAX NFI observations
  74. GRB 991014, Optical Observations
  75. GRB 990915 optical observations
  76. GRB990907: BeppoSAX follow up and X-ray afterglow
  77. GRB 990712 Late Optical Decay and Host Galaxy
  78. GRB 990712, Optical Observation
  79. GRB990806 BeppoSAX follow up
  80. GRB990806: possible X-ray afterglow, BeppoSAX
  81. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  82. GRB 990705, radio observations
  83. GRB990704: SAX-NFI results summary
  84. BeppoSAX GRB990705: possible X-ray afterglow
  85. GRB990704: possible X-ray afterglow
  86. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  87. GRB 990627, radio observations
  88. GRB 990506 Radio Transient
  89. Late Afterglows of GRBs 990510, 990123
  90. GRB990510: X-ray afterglow
  91. GRB 990510: Broad Band Break
  92. GRB990510: NFI X-ray source
  93. GRB 990506: BATSE Observations
  94. IPN localization for GRB990506
  95. GRB981220 VLBA observations
  96. GRB990316: simultaneous optical observation
  97. GRB 981220, radio observations
  98. GRB990123, Optical Observation
  99. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  100. GRB 990123: Detection of the IR Transient, and the Light Curve Fits

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