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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').

31197 results found.

  1. GRB 990123: New Constraints on Possible Foreground Galaxies
  2. GRB990123 Optical Observations
  3. GRB990123, Probability of gravitational lensing
  4. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  5. GRB 990123: Continued Radio Observations
  6. GRB990123, Preliminary Lens Search Results
  7. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  8. On the Lensing Interpretation of GRB 990123
  9. Search for Potential Images of GRB 990123
  10. Search for Potential Images of GRB 990123
  11. GRB990123, Optical BVRI Observations
  12. GRB 990123: near-infrared observations.
  13. GRB990123, OSSE observations
  14. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  15. "GRB 990123: New BV Observations"
  16. GRB 990123 Optical Follow-Up
  17. GRB 990123; Addendum to GCN 223
  18. GRB 990123: BATSE Observations
  19. GRB 990123 Keck Spectrum update
  20. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  21. GRB990123 Optical Observations
  22. GRB 990123 Spectroscopic Redshifts
  23. GRB 990123: New Optical Observations, Decay Measure
  24. GRB 990123 Optical Follow-Up
  25. GRB 990123: Possible Gravitationally Lensed Burst?
  26. GRB 990123 optical observations
  27. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  28. GRB 990123 radio observations
  29. GRB 990123, new radio source
  30. GRB990123, Optical observation
  31. GRB 990123: Optical Decay Slope
  32. GRB 990123 r-band photometry
  33. GRB 990123 Optical Follow-up
  34. GRB990123, early optical counterpart detection
  35. GRB990123 Optical Observation
  36. GRB 990123: Bright New Source, Possible Optical Transient
  37. GRB 990123, Radio observations
  38. SN 1999E & GRB 980919
  39. Possible identification of SN1999E with GRB980910
  40. Optical Observations of GRB 981220
  41. GRB 981226: radio variable
  42. GRB981220
  43. GRB981220, Optical Observations
  44. GRB 981220 Optical observations
  45. GRB 981226 Optical Observations
  46. GRB 980613: Spectroscopy of the host galaxy
  47. GRB981226, sub-millimeter observations
  48. GRB981220, sub-millimeter observations
  49. GRB 981220 and GRB 981226, optical observations
  50. GRB 981226 radio observations
  51. GRB 981226
  52. GRB 981226 optical observations
  53. radio observations of GRB 981226
  54. GRB981220 B, R and I band observations
  55. GRB 981220:Optical Observations
  56. GRB 981220 optical R and I observations
  57. GRB981226, BeppoSAX Christmas GRB
  58. GRB 981226 - Infrared Observations
  59. GRB 981226 optical observations
  60. GRB 981220
  61. GRB 981220, radio observations
  62. GRB981226 Optical Observation
  63. GRB 981220, radio observations
  64. GRB 981220: BeppoSAX/GRBM results
  65. GRB981220 I-band Observations
  66. GRB 981220
  67. GRB 981220 Optical Observations
  68. GRB 981220, optical observations
  69. GRB 980326/Host Galaxy
  70. GRB981220 IPN error box
  71. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  72. GRB980329 R,I flux calibration and R,I,K upper limits
  73. GRB980425: X-ray revised positions
  74. GRB 980923 BATSE Observations
  75. GRB980703 Very Long Baseline Interferometry
  76. GRB970508 optical observations
  77. GRB971214, association with a Galactic star?
  78. Optical Observations of the Host Galaxy of GRB 980519
  79. GRB980519, Optical Observations
  80. GRB980703, Host galaxy multicolor photometry
  81. GRB980703 - BeppoSAX/GRBM detection
  82. GRB 980703 (NFI observations)
  83. GRB980703 optical photometry
  84. GRB 980703: BATSE Observations
  85. GRB980703: Radio transient
  86. GRB980703 H-band Observations
  87. GRB 980703: Spectrum of the proposed optical counterpart
  88. RXTE Observation of GRB 980706
  89. GRB980703: Spectrum of the proposed optical counterpart
  90. GRB980703 Transient Optical Follow-Up
  91. GRB980703: LOTIS observation at early times
  92. GRB980613 Optical Observations
  93. GRB 980703
  94. GRB 980703 H-band Observations
  95. GRB980703 (optical R observations)
  96. GRB980706
  97. GRB980703: radio source/optical transient
  98. BeppoSAX NFI observations of GRB 980703
  99. GRB 980703: ASM Position & Intensity
  100. GRB980703

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