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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"

34071 results found.

  1. GRB 990510: optical linear polarization
  2. GRB 990510: optical observations
  3. GRB990510, VI observations
  4. GRB 990506 R band observations
  5. GRB990510: X-ray afterglow
  6. GRB 990510: optical observation
  7. VLT spectrum of GRB990510
  8. GRB 990510: Broad Band Break
  9. GRB 990510: BATSE Observations
  10. GRB 990510 Optical Observations
  11. GRB 990510, BVI photometry
  12. GRB 990510 optical observations
  13. GRB 990510: BeppoSAX/GRBM observations
  14. GRB990510 optical observations
  15. GRB 990510 optical observations
  16. GRB 990510 optical observations
  17. Galactic extinction towards GRB 990510
  18. GRB 990510 optical observations
  19. IPN localization of GRB990510
  20. GRB 990506 Radio Observations
  21. GRB 990123, optical monitoring
  22. GRB 990506: BATSE Observations
  23. GRB 990506, optical observations
  24. GRB 990510: Final BeppoSAX-WFC Coordinates
  25. GRB 990506, Optical Observations
  26. GRB 990506 optical observations
  27. GRB 990506 optical observations
  28. GRB 990506, optical observations
  29. GRB990506 observation plan
  30. Refined IPN error box for GRB990506
  31. GRB 990506: Limits on the possible optical transient
  32. GRB 990506, armchair astronomy
  33. GRB 990506, optical observations from +1 to +3 hours
  34. GRB 990506, optical observations
  35. GRB990506 observation plan
  36. New IPN/RXTE error box for GRB990506
  37. IPN localization for GRB990506
  38. GRB 970228: Redshift and properties of the host galaxy
  39. IPN localization of GRB990427
  40. GRB981220 VLBA observations
  41. GRB990321 REFINED IPN ANNULUS
  42. GRB990323 PRECISE IPN POSITION
  43. GRB990321 IPN TRIANGULATION
  44. GRB 990316 Optical Observations
  45. GRB 990316, Radio observations
  46. GRB 990316, Optical observations
  47. GRB990316, Optical observations
  48. GRB 990316 optical observations
  49. GRB990316: simultaneous optical observation
  50. ASM/IPN error box for GRB 990308 (BATSE #7457)
  51. GRB990308 not a new SGR
  52. GRB 990308a and GRB 990308b
  53. GRB990308 (Trig. 7457), optical observations
  54. GRB981220, IPN localization
  55. GRB 981220, radio observations
  56. GRB 990123, Field Photometry
  57. GRB 990217 Optical Observations
  58. GRB 990217, radio observations
  59. Optical Observations of GRB990217
  60. GRB990123: Caltech STIS Photometry and Images
  61. GRB990123 observations
  62. GRB990123, Optical Observation
  63. GRB 990123: Discovery of the Probable Host Galaxy
  64. GRB 990123: Reduced HST Images
  65. For Immediate Posting to GCN - HST Data GRB 990123 Available
  66. GRB19990123 observations
  67. GRB 990123: BVRI standards in the field
  68. GRB 990123: Updated Keck Spectroscopy Results
  69. GRB981220, field photometry
  70. GRB 990123 NOT Spectrum Update
  71. GRB990123, Optical observation
  72. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  73. GRB 990123: Publicly available reduced HST images
  74. GRB990123, Upcoming HST Service Observations
  75. GRB 990123: New Constraints on Possible Foreground Galaxies
  76. GRB990123 Optical Observations
  77. GRB990123, Probability of gravitational lensing
  78. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  79. GRB 990123: Continued Radio Observations
  80. GRB990123, Preliminary Lens Search Results
  81. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  82. On the Lensing Interpretation of GRB 990123
  83. Search for Potential Images of GRB 990123
  84. Search for Potential Images of GRB 990123
  85. GRB990123, Optical BVRI Observations
  86. GRB 990123: near-infrared observations.
  87. GRB990123, OSSE observations
  88. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  89. "GRB 990123: New BV Observations"
  90. GRB 990123 Optical Follow-Up
  91. GRB 990123; Addendum to GCN 223
  92. GRB 990123: BATSE Observations
  93. GRB 990123 Keck Spectrum update
  94. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  95. GRB990123 Optical Observations
  96. GRB 990123 Spectroscopic Redshifts
  97. GRB 990123: New Optical Observations, Decay Measure
  98. GRB 990123 Optical Follow-Up
  99. GRB 990123: Possible Gravitationally Lensed Burst?
  100. GRB 990123 optical observations

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