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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"

38349 results found.

  1. GRB 981220, radio observations
  2. GRB 990217 Optical Observations
  3. GRB 990217, radio observations
  4. BATSE Flight Anomaly
  5. GRB990217: BeppoSAX/GRBM data
  6. Optical Observations of GRB990217
  7. GRB990123: Caltech STIS Photometry and Images
  8. GRB990123 observations
  9. GRB990217 Optical observation
  10. GRB990217, WFC position
  11. GRB990123, Optical Observation
  12. GRB 990123: Discovery of the Probable Host Galaxy
  13. GRB 990123: Reduced HST Images
  14. GRB19990123 observations
  15. GRB 990123: Updated Keck Spectroscopy Results
  16. GRB981220, field photometry
  17. GRB 990123 NOT Spectrum Update
  18. GRB990123, Optical observation
  19. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  20. GRB 990123: Publicly available reduced HST images
  21. GRB990123, Upcoming HST Service Observations
  22. GRB 990123: New Constraints on Possible Foreground Galaxies
  23. GRB990123 Optical Observations
  24. GRB990123, Probability of gravitational lensing
  25. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  26. GRB 990123: Continued Radio Observations
  27. GRB990123, Preliminary Lens Search Results
  28. On the Lensing Interpretation of GRB 990123
  29. Search for Potential Images of GRB 990123
  30. Search for Potential Images of GRB 990123
  31. GRB990123, Optical BVRI Observations
  32. GRB 990123: near-infrared observations.
  33. GRB990123, OSSE observations
  34. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  35. GRB990123: NIR Observation
  36. "GRB 990123: New BV Observations"
  37. GRB 990123 Optical Follow-Up
  38. GRB 990123: BATSE Observations
  39. GRB 990123 Keck Spectrum update
  40. GRB990123 IPN annulus
  41. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  42. GRB 990123 Spectroscopic Redshifts
  43. GRB 990123: New Optical Observations, Decay Measure
  44. GRB 990123 Optical Follow-Up
  45. GRB 990123: Possible Gravitationally Lensed Burst?
  46. GRB990123, optical observation
  47. GRB 990123 optical observations
  48. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  49. GRB 990123 radio observations
  50. GRB 990123, new radio source
  51. GRB990123 optical observations
  52. GRB990123, Optical observation
  53. GRB 990123: Optical Decay Slope
  54. GRB 990123 r-band photometry
  55. GRB 990123 Optical Follow-up
  56. GRB990123, early optical counterpart detection
  57. GRB990123 Optical Observation
  58. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  59. GRB990123, refined SAX-WFC position
  60. GRB 990123: Bright New Source, Possible Optical Transient
  61. GRB 990123, Radio observations
  62. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  63. Possible identification of SN1999E with GRB980910
  64. Optical Observations of GRB 981220
  65. GRB 981226: radio variable
  66. GRB981220
  67. GRB981220, Optical Observations
  68. GRB 981220 Optical observations
  69. GRB 981226 Optical Observations
  70. GRB 980613: Spectroscopy of the host galaxy
  71. GRB981226, sub-millimeter observations
  72. GRB981220, sub-millimeter observations
  73. GRB 981220 and GRB 981226, optical observations
  74. GRB981226 Optical Observations
  75. GRB981226 BeppoSAX follow up
  76. GRB 981226 radio observations
  77. GRB 981226
  78. GRB 981226 optical observations
  79. radio observations of GRB 981226
  80. GRB981220 B, R and I band observations
  81. GRB981226, BeppoSAX-NFI follow-up
  82. Optical Observations of GRB981226
  83. GRB 981220:Optical Observations
  84. GRB981226, BeppoSAX Christmas GRB
  85. GRB 981226 - Infrared Observations
  86. GRB 981220
  87. GRB 981220, radio observations
  88. GRB981226 Optical Observation
  89. GRB 981220, radio observations
  90. GRB 981220: BeppoSAX/GRBM results
  91. GRB981220 I-band Observations
  92. GRB981220 Optical Observations
  93. GRB 981220
  94. GRB 981220 Optical Observations
  95. GRB 981220, optical observations
  96. GRB 980326/Host Galaxy
  97. GRB981220 IPN error box
  98. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  99. BeppoSAX NFI Observation of GRB980425
  100. GRB980329 R,I flux calibration and R,I,K upper limits

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