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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"

40637 results found.

  1. GRB 990123 NOT Spectrum Update
  2. GRB990123, Optical observation
  3. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  4. GRB 990123: Publicly available reduced HST images
  5. GRB990123, Upcoming HST Service Observations
  6. GRB990123, 15-GHz limits
  7. GRB 990123: New Constraints on Possible Foreground Galaxies
  8. GRB990123 Optical Observations
  9. GRB990123, Probability of gravitational lensing
  10. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  11. GRB 990123: Continued Radio Observations
  12. GRB990123, Preliminary Lens Search Results
  13. On the Lensing Interpretation of GRB 990123
  14. Search for Potential Images of GRB 990123
  15. Search for Potential Images of GRB 990123
  16. GRB990123, Optical BVRI Observations
  17. GRB 990123: near-infrared observations.
  18. GRB990123, OSSE observations
  19. GRB990123: NIR Observation
  20. GRB990123, ASCA X-ray observation of afterglow
  21. "GRB 990123: New BV Observations"
  22. GRB 990123 Optical Follow-Up
  23. GRB 990123; Addendum to GCN 223
  24. GRB 990123: BATSE Observations
  25. GRB 990123 Keck Spectrum update
  26. GRB990123 IPN annulus
  27. GRB990123 Optical Observations
  28. GRB 990123 Spectroscopic Redshifts
  29. GRB 990123: New Optical Observations, Decay Measure
  30. GRB 990123 Optical Follow-Up
  31. GRB 990123: Possible Gravitationally Lensed Burst?
  32. GRB990123, optical observation
  33. GRB 990123 optical observations
  34. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  35. GRB 990123 radio observations
  36. GRB 990123, new radio source
  37. GRB990123 optical observations
  38. GRB990123, Optical observation
  39. GRB 990123: Optical Decay Slope
  40. GRB 990123 r-band photometry
  41. GRB 990123 Optical Follow-up
  42. GRB990123 Optical Observation
  43. GRB990123, refined SAX-WFC position
  44. GRB 990123: Bright New Source, Possible Optical Transient
  45. GRB 990123, Radio observations
  46. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  47. SN 1999E & GRB 980919
  48. Possible identification of SN1999E with GRB980910
  49. Optical Observations of GRB 981220
  50. GRB 981226: radio variable
  51. GRB981220
  52. GRB981220, Correction to GCN 179
  53. GRB981220, Optical Observations
  54. GRB 981220 Optical observations
  55. GRB 981226 Optical Observations
  56. GRB 980613: Spectroscopy of the host galaxy
  57. GRB981226, sub-millimeter observations
  58. GRB981220, sub-millimeter observations
  59. GRB 981220 and GRB 981226, optical observations
  60. GRB981226 Optical Observations
  61. GRB981226 BeppoSAX follow up
  62. GRB 981226 radio observations
  63. GRB 981226
  64. GRB 981226 optical observations
  65. radio observations of GRB 981226
  66. GRB981220 B, R and I band observations
  67. GRB981226, BeppoSAX-NFI follow-up
  68. Optical Observations of GRB981226
  69. GRB 981220:Optical Observations
  70. GRB 981220 optical R and I observations
  71. GRB981226, BeppoSAX Christmas GRB
  72. GRB 981226 - Infrared Observations
  73. GRB 981226 optical observations
  74. GRB 981220
  75. GRB 981220, radio observations
  76. GRB981226 Optical Observation
  77. GRB 981220, radio observations
  78. GRB 981220: BeppoSAX/GRBM results
  79. GRB981220 I-band Observations
  80. GRB981220 Optical Observations
  81. GRB 981220
  82. GRB 981220 Optical Observations
  83. GRB 981220, optical observations
  84. GRB 980326/Host Galaxy
  85. GRB981220 IPN error box
  86. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  87. BeppoSAX NFI Observation of GRB980425
  88. GRB980329 R,I flux calibration and R,I,K upper limits
  89. GRB980425 Optical Follow-up
  90. GRB980425: X-ray revised positions
  91. GRB 980923 BATSE Observations
  92. SGR1900+14, BeppoSAX-GRBM observations
  93. GRB980703 Very Long Baseline Interferometry
  94. GRB970508 optical observations
  95. GRB971214, association with a Galactic star?
  96. Optical Observations of the Host Galaxy of GRB 980519
  97. GRB980519, Optical Observations
  98. GRB980703, Host galaxy multicolor photometry
  99. GRB 980703 (NFI observations)
  100. GRB980703 optical photometry

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