ETC Request ID: STIS.sp.1008100

Exposure time (seconds) = 2,802.0000 at wavelength 1550.00 Å

gives: SNR = 117.1814 (per resolution element)

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: MAMA Bright limits: total count rate per image 189058 exceeds limit for irregularly-variable sources 40 percent of the bright limit 200000 counts per second

WARNING MESSAGE: Buffer time 10.5788 is less than minimum 99 seconds.


Table of Source and Noise Counts per Pixel

Plots

Detailed Information Count rate Total counts Associated noise
(counts/s) (counts) (counts)
Counts (box 7 pixels high) (1 pix x 7 pix) (2 pix resel x 7 pix)
    Source 2.650 14,850.29 121.86
    Background 0.001 5.88 2.43
        Sky 7.176e-14 4.02e-10 2.01e-05
        Dark Current 0.001 5.88 2.43
Total in selected region 2.651 14,856.17 126.73
Brightest Pixel (single exposure) (at 1399.50 Å) 2.499 7,002.16
Count rate entire detector 189,057.983
Buffer Time (sec) 10.58
For APT purposes, the recommended buffer time should be 4/5 of the buffer time calculated above. Please refer to the STIS Instrument Handbook for more details.
Global Count Rates
    Source only 125,933.831 352,866,593.627
    Background (sky+dark) 157.286 440,716.49
Encircled energy fraction 0.94

Instrument name: STIS
Mode: spectroscopic
Detector: FUVMAMA
Central Wavelength: 1489
Grating: [E140H] R ~ 114000
Aperture: 0.2X0.09
Glow region: low


Target: [point source]
Spectrum: User uploaded spectrum: hd32309-iue.txt
Extinction E(B-V): None
Normalization: None
Redshift: None
Emission Lines: None


Selected background:
  Sky Background:
    Level:

Table of Source and Noise Counts per Pixel

Plots

These results were computed using: ETC version 25.2