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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').
  1. On the Lensing Interpretation of GRB 990123
  2. Search for Potential Images of GRB 990123
  3. Search for Potential Images of GRB 990123
  4. GRB990123, Optical BVRI Observations
  5. GRB 990123: near-infrared observations.
  6. GRB990123, OSSE observations
  7. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  8. GRB990123: NIR Observation
  9. GRB990123, ASCA X-ray observation of afterglow
  10. "GRB 990123: New BV Observations"
  11. GRB 990123 Optical Follow-Up
  12. GRB 990123; Addendum to GCN 223
  13. GRB 990123: BATSE Observations
  14. GRB 990123 Keck Spectrum update
  15. GRB990123 IPN annulus
  16. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  17. GRB990123 Optical Observations
  18. GRB 990123 Spectroscopic Redshifts
  19. GRB 990123: New Optical Observations, Decay Measure
  20. GRB 990123 Optical Follow-Up
  21. GRB 990123: Possible Gravitationally Lensed Burst?
  22. GRB990123, optical observation
  23. GRB 990123 optical observations
  24. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  25. GRB 990123 radio observations
  26. GRB 990123, new radio source
  27. GRB990123 optical observations
  28. GRB990123, Optical observation
  29. GRB 990123: Optical Decay Slope
  30. GRB 990123 r-band photometry
  31. GRB 990123 Optical Follow-up
  32. GRB990123, early optical counterpart detection
  33. GRB990123 Optical Observation
  34. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  35. GRB990123, refined SAX-WFC position
  36. GRB 990123: Bright New Source, Possible Optical Transient
  37. GRB 990123, Radio observations
  38. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  39. SN 1999E & GRB 980919
  40. Possible identification of SN1999E with GRB980910
  41. Optical Observations of GRB 981220
  42. GRB 981226: radio variable
  43. GRB981220
  44. GRB981220, Correction to GCN 179
  45. GRB981220, Optical Observations
  46. GRB 981220 Optical observations
  47. GRB 981226 Optical Observations
  48. GRB 980613: Spectroscopy of the host galaxy
  49. GRB981226, sub-millimeter observations
  50. GRB981220, sub-millimeter observations
  51. GRB 981220 and GRB 981226, optical observations
  52. GRB981226 Optical Observations
  53. GRB981226 BeppoSAX follow up
  54. GRB 981226 radio observations
  55. GRB 981226
  56. GRB 981226 optical observations
  57. radio observations of GRB 981226
  58. GRB981220 B, R and I band observations
  59. GRB981226, BeppoSAX-NFI follow-up
  60. Optical Observations of GRB981226
  61. GRB 981220:Optical Observations
  62. GRB 981220 optical R and I observations
  63. GRB981226, BeppoSAX Christmas GRB
  64. GRB 981226 - Infrared Observations
  65. GRB 981226 optical observations
  66. GRB 981220
  67. GRB 981220, radio observations
  68. GRB981226 Optical Observation
  69. GRB 981220, radio observations
  70. GRB 981220: BeppoSAX/GRBM results
  71. GRB981220 I-band Observations
  72. GRB981220 Optical Observations
  73. GRB 981220
  74. GRB 981220 Optical Observations
  75. GRB 981220, optical observations
  76. GRB 980326/Host Galaxy
  77. GRB981220 IPN error box
  78. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  79. BeppoSAX NFI Observation of GRB980425
  80. GRB980329 R,I flux calibration and R,I,K upper limits
  81. GRB980425 Optical Follow-up
  82. GRB980425: X-ray revised positions
  83. GRB 980923 BATSE Observations
  84. SGR1900+14, BeppoSAX-GRBM observations
  85. GRB980703 Very Long Baseline Interferometry
  86. GRB970508 optical observations
  87. GRB971214, association with a Galactic star?
  88. Optical Observations of the Host Galaxy of GRB 980519
  89. GRB980519, Optical Observations
  90. GRB980703, Host galaxy multicolor photometry
  91. GRB980703 - BeppoSAX/GRBM detection
  92. GRB 980703 (NFI observations)
  93. GRB980703 optical photometry
  94. GRB 980703: BATSE Observations
  95. GRB980703 optical observations
  96. GRB980703: Radio transient
  97. GRB980703 H-band Observations
  98. GRB 980703: Spectrum of the proposed optical counterpart
  99. RXTE Observation of GRB 980706
  100. GRB980703: Spectrum of the proposed optical counterpart

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