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Table 4
Upper limits (2σ, in units 10-5 ph cm-2 s-1) for 511 keV gamma-ray line emission originating from the Crab or Cyg X-1.
| Narrow line | Broad line | |
| Crab | 6.62 | 7.44 |
| Cyg X-1 | 1.27 | 1.89 |
Notes. Limits for a narrow (1.6 keV FWHM), and a broad line (3.5 keV FWHM) are given.
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