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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').

23921 results found.

  1. GRB 000926: Preliminary R-band Lightcurve
  2. Spectroscopic Redshift of GRB 000926
  3. GRB 000926: Optical candidate
  4. Optical candidate for GRB000926
  5. GRB 000911, BVRI field photometry
  6. GRB000911, Radio and Optical observations
  7. GRB000911: Optical observations
  8. GRB000830, BVRI field photometry
  9. GRB000210, Optical observations
  10. "Snapshot" afterglow IDs and GRB 000830
  11. GRB000730, Gamma Ray Observations
  12. GRB000812, Radio observations
  13. GRB000801, Gamma Ray Observations
  14. GRB000801, VLT-Antu R-band observations
  15. GRB 991208 Host Galaxy Imaging
  16. IPN localization of GRB000730B
  17. GRB 990510: Possible detection of a host galaxy
  18. GRB 990510 Host Galaxy Discovery
  19. IPN localization of GRB000727
  20. GRB 990712: Late time HST/STIS Observations
  21. GRB 991216, HST/STIS observations
  22. GRB000620, Radio Observations
  23. GRB000630, optical observations
  24. GRB000630, Revised BVRI Field Photometry
  25. GRB000630, Optical Observations
  26. GRB000630, optical observations
  27. GRB000630, optical observations
  28. GRB000630, BVRI Field Photometry
  29. GRB000630, optical observations
  30. GRB000630: Optical observations
  31. GRB000630, Radio Observations
  32. possible optical counterpart of GRB 000630
  33. GRB 000620, optical observations
  34. GRB000418, HST/STIS Observations
  35. GRB990123: Late-time HST/STIS observations of the host
  36. GRB000620, optical observations
  37. GRB000615: H-band observations
  38. GRB990308, HST/STIS observations of the host galaxy
  39. GRB000620 - Optical observations
  40. GRB000620 Optical observations
  41. GRB000620: BeppoSAX WFC and GRBM detection
  42. GRB000607, optical observations
  43. GRB 000615: NIR further observations
  44. GRB990123, HST/STIS observations of the host galaxy
  45. GRB000616 optical observations
  46. GRB 000615, near-infrared observations
  47. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  48. GRB000615, further R-band photometry
  49. GRB 000615: NIR observations
  50. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  51. GRB000615, R-band photometry
  52. The Hosts of GRB 980703 and GRB 971214
  53. GRB 000301C: Further Late-Time HST/STIS observations
  54. GRB000528: follow-up X-ray measurements and update of IPN annulus
  55. GRB980519, HST/STIS observations of the host galaxy
  56. GRB000604 optical non-detection
  57. GRB000604 - Optical observations
  58. GRB000604, optical observations
  59. GRB000528, optical observations at ESO
  60. GRB 000604 optical observations
  61. GRB 000418: Detection of the Host Galaxy
  62. GRB000604, optical observations, comparison with DPOSS
  63. GRB000528, Radio Observations
  64. X-ray Afterglow of GRB 000529
  65. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  66. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  67. GRB 000528 - WFC measurements
  68. GRB000519, BVRI field photometry
  69. IPN triangulation of GRB000519
  70. GRB000508B, optical photometry
  71. GRB000508B, BVR field photometry
  72. Possible GRB-related phenomenon
  73. RXTE/ASM and IPN localization of GRB 000508B
  74. GRB000424, UBVRI field photometry
  75. GRB000418, UBVRI field photometry update
  76. GRB000424, optical observations
  77. GRB 000429, optical observation
  78. GRB 000429, UBVRI field photometry
  79. GRB 000418, UBVRI field photometry
  80. GRB 000418, optical observation
  81. GRB 000418, Optical Observation
  82. GRB000418, near-infrared observations
  83. Correction to IPN error box for GRB000419
  84. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  85. GRB000416 BRJK observations
  86. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  87. GRB 000408, optical observations
  88. GRB 991208, UBVRI field photometry
  89. GRB000408, lotis optical observations
  90. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  91. GRB000301C - Addendum to GCN 623
  92. GRB 000323, optical observations
  93. GRB 000326: Optical Observations
  94. GRB000326, Radio observations
  95. GRB000313, Radio observations
  96. GRB 000313 - optical transient in the BATSE error box
  97. GRB 000307, Optical Observations
  98. GRB 000307, BVRI Field Photometry
  99. GRB 000301C: A Precise Redshift Determination
  100. GRB 000301C, Optical Observation

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