ETC Request ID: STIS.sp.1166537

Exposure time (seconds) = 380.0000 at wavelength 9428.00 Å

gives: SNR = 791.9472 (per resolution element)

gives: Time to Saturation (for a single exposure) = 69.20 seconds

Exposure time calculation HAD WARNINGS.

WARNING MESSAGE: CCD Full Well limits: total counts per native pixel 181201 exceeds bright limit 33000 for selected gain

WARNING MESSAGE: "Electrons per pixel due to background (9.5) is less than the recommended threshold of 20 electrons to avoid poor charge transfer efficiency (CTE). We suggest you consider CTE mitigation strategies described in the STIS Instrument Handbook."


Table of Source and Noise Counts per Pixel

Plots

Detailed Information Count rate Total counts Associated noise
(e-/s) (e-) (e-)
Counts (box 7 pixels high) (1 pix x 7 pix) (2 pix resel x 7 pix)
    Source 826.097 627,833.72 792.36
    Background 0.175 133.04 11.53
        Sky 4.950e-05 0.04 0.19
        Dark Current 0.175 133.00 11.53
    Read Out 22.82
Total in selected region 826.272 627,966.76 792.77
Brightest Pixel (single exposure) (at 9050.55 Å) 476.846 181,201.36
Global Count Rates
    Source only 1,295,789.386 492,399,966.563
    Background (sky+dark) 26,222.337 9,964,488.15
Encircled energy fraction 0.69

Instrument name: STIS
Mode: spectroscopic
Detector: CCD
Central Wavelength: 9336
Grating: [G750M] R ~ 5000
Aperture: 52X0.1
Gain: 1.0
# Frames: 1
Binning: dispersion: 1, spatial: 1
Dark: medium


Target: [point source]
Spectrum: Kurucz Models B3V 18700 3.9
Extinction E(B-V): Milky Way Diffuse (Rv=3.1) = 0.9 applied before normalization
Normalization: Renormalized to vegamag = 5.7 in filter Johnson/J
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 26.1