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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"

35429 results found.

  1. GRB 990316 Optical Observations
  2. GRB 990316, Radio observations
  3. GRB 990316, Optical observations
  4. GRB990316, Optical observations
  5. GRB 990316 optical observations
  6. GRB990316: simultaneous optical observation
  7. ASM/IPN error box for GRB 990308 (BATSE #7457)
  8. GRB990308 not a new SGR
  9. GRB 990308a and GRB 990308b
  10. GRB990308 (Trig. 7457), optical observations
  11. GRB981220, IPN localization
  12. GRB 981220, radio observations
  13. GRB 990123, Field Photometry
  14. GRB 990217 Optical Observations
  15. GRB 990217, radio observations
  16. Optical Observations of GRB990217
  17. GRB990123: Caltech STIS Photometry and Images
  18. GRB990123 observations
  19. GRB990123, Optical Observation
  20. GRB 990123: Discovery of the Probable Host Galaxy
  21. GRB 990123: Reduced HST Images
  22. For Immediate Posting to GCN - HST Data GRB 990123 Available
  23. GRB19990123 observations
  24. GRB 990123: BVRI standards in the field
  25. GRB 990123: Updated Keck Spectroscopy Results
  26. GRB981220, field photometry
  27. GRB 990123 NOT Spectrum Update
  28. GRB990123, Optical observation
  29. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  30. GRB 990123: Publicly available reduced HST images
  31. GRB990123, Upcoming HST Service Observations
  32. GRB 990123: New Constraints on Possible Foreground Galaxies
  33. GRB990123 Optical Observations
  34. GRB990123, Probability of gravitational lensing
  35. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  36. GRB 990123: Continued Radio Observations
  37. GRB990123, Preliminary Lens Search Results
  38. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  39. On the Lensing Interpretation of GRB 990123
  40. Search for Potential Images of GRB 990123
  41. Search for Potential Images of GRB 990123
  42. GRB990123, Optical BVRI Observations
  43. GRB 990123: near-infrared observations.
  44. GRB990123, OSSE observations
  45. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  46. "GRB 990123: New BV Observations"
  47. GRB 990123 Optical Follow-Up
  48. GRB 990123; Addendum to GCN 223
  49. GRB 990123: BATSE Observations
  50. GRB 990123 Keck Spectrum update
  51. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  52. GRB990123 Optical Observations
  53. GRB 990123 Spectroscopic Redshifts
  54. GRB 990123: New Optical Observations, Decay Measure
  55. GRB 990123 Optical Follow-Up
  56. GRB 990123: Possible Gravitationally Lensed Burst?
  57. GRB 990123 optical observations
  58. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  59. GRB 990123 radio observations
  60. GRB 990123, new radio source
  61. GRB990123, Optical observation
  62. GRB 990123: Optical Decay Slope
  63. GRB 990123 r-band photometry
  64. GRB 990123 Optical Follow-up
  65. GRB990123, early optical counterpart detection
  66. GRB990123 Optical Observation
  67. GRB 990123: Bright New Source, Possible Optical Transient
  68. GRB 990123, Radio observations
  69. SN 1999E & GRB 980919
  70. Possible identification of SN1999E with GRB980910
  71. Optical Observations of GRB 981220
  72. GRB 981226: radio variable
  73. GRB981220
  74. GRB981220, Optical Observations
  75. GRB 981220 Optical observations
  76. GRB 981226 Optical Observations
  77. GRB 980613: Spectroscopy of the host galaxy
  78. GRB981226, sub-millimeter observations
  79. GRB981220, sub-millimeter observations
  80. GRB 981220 and GRB 981226, optical observations
  81. GRB 981226 radio observations
  82. GRB 981226
  83. GRB 981226 optical observations
  84. radio observations of GRB 981226
  85. GRB981220 B, R and I band observations
  86. GRB 981220:Optical Observations
  87. GRB 981220 optical R and I observations
  88. GRB981226, BeppoSAX Christmas GRB
  89. GRB 981226 - Infrared Observations
  90. GRB 981226 optical observations
  91. GRB 981220
  92. GRB 981220, radio observations
  93. GRB981226 Optical Observation
  94. GRB 981220, radio observations
  95. GRB 981220: BeppoSAX/GRBM results
  96. GRB981220 I-band Observations
  97. GRB 981220
  98. GRB 981220 Optical Observations
  99. GRB 981220, optical observations
  100. GRB 980326/Host Galaxy

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