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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"

32489 results found.

  1. GRB990308 not a new SGR
  2. GRB 990308a and GRB 990308b
  3. GRB990308 (Trig. 7457), optical observations
  4. GRB981220, IPN localization
  5. GRB 981220, radio observations
  6. GRB 990123, Field Photometry
  7. GRB 990217, radio observations
  8. BATSE Resumes Normal Operations
  9. BATSE Flight Anomaly
  10. GRB990123: Caltech STIS Photometry and Images
  11. GRB990123 observations
  12. GRB990123, Optical Observation
  13. GRB 990123: Discovery of the Probable Host Galaxy
  14. GRB 990123: Reduced HST Images
  15. For Immediate Posting to GCN - HST Data GRB 990123 Available
  16. GRB19990123 observations
  17. GRB 990123: Updated Keck Spectroscopy Results
  18. GRB 990123 NOT Spectrum Update
  19. GRB990123, Optical observation
  20. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  21. GRB 990123: Publicly available reduced HST images
  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. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  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. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  34. GRB990123: NIR Observation
  35. "GRB 990123: New BV Observations"
  36. GRB 990123 Optical Follow-Up
  37. GRB 990123; Addendum to GCN 223
  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. GRB990123 Optical Observations
  43. GRB 990123 Spectroscopic Redshifts
  44. GRB 990123: New Optical Observations, Decay Measure
  45. GRB 990123 Optical Follow-Up
  46. GRB 990123: Possible Gravitationally Lensed Burst?
  47. GRB990123, optical observation
  48. GRB 990123 optical observations
  49. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  50. GRB 990123 radio observations
  51. GRB 990123, new radio source
  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. GRB 990123: Bright New Source, Possible Optical Transient
  59. GRB 990123, Radio observations
  60. SN 1999E & GRB 980919
  61. Optical Observations of GRB 981220
  62. GRB 981226: radio variable
  63. GRB981220
  64. GRB981220, Correction to GCN 179
  65. GRB981220, Optical Observations
  66. GRB 981220 Optical observations
  67. GRB 981226 Optical Observations
  68. GRB 980613: Spectroscopy of the host galaxy
  69. GRB981226, sub-millimeter observations
  70. GRB981220, sub-millimeter observations
  71. GRB 981220 and GRB 981226, optical observations
  72. GRB981226 Optical Observations
  73. GRB 981226 radio observations
  74. GRB 981226
  75. radio observations of GRB 981226
  76. GRB981220 B, R and I band observations
  77. Optical Observations of GRB981226
  78. GRB 981220:Optical Observations
  79. GRB 981220 optical R and I observations
  80. GRB981226, BeppoSAX Christmas GRB
  81. GRB 981226 - Infrared Observations
  82. GRB 981220
  83. GRB 981220, radio observations
  84. GRB 981220, radio observations
  85. GRB 981220: BeppoSAX/GRBM results
  86. GRB981220 I-band Observations
  87. GRB 981220
  88. GRB 981220 Optical Observations
  89. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  90. BeppoSAX NFI Observation of GRB980425
  91. GRB980425 Optical Follow-up
  92. GRB980425: X-ray revised positions
  93. GRB980703 Very Long Baseline Interferometry
  94. GRB970508 optical observations
  95. Optical Observations of the Host Galaxy of GRB 980519
  96. GRB980519, Optical Observations
  97. GRB980703, Host galaxy multicolor photometry
  98. GRB 980703 (NFI observations)
  99. GRB980703 optical photometry
  100. GRB 980703: BATSE Observations

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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