[Temperature response func.] = [Factor(geometrical, etc.)] * [Model Solar Spectra] # [XRT Effective Area]
(T) (T, λ) (λ)
[Effective Area] = [aperture] * [prefilter] * [mirror1] * [mirror2] * [filter1] * [filter2] * [ccdqe] * [contamination]aperture=2.28 cm^2
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Effective Area modified partially opened prefilter (without X-ray filters).
| Open/Al-mesh | Open/Ti-poly |
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| Al-poly/Open | Thin-Be/Open |
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| Open/thick-Al | Open/thick-Be |
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| Al-poly/Al-mesh | Ti-poly/Al-mesh |
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| thin-Be/Al-poly | thick-Be/thick-Al |
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VLI transmission from the Blue Book section 2.5.1.
The VLI transmission should not be the peak value (0.026) but the averaged value (0.020) over the band width (since Nov-2025). In addition, the effective area of G-band optics was initially assumed as 25mm*25mm*3.14, from the size of G-band lens (having 50mm diameter). However, the actual value should be smaller because of the way it is mounted in a long housing tube. The new value of VLI effective area is 20mm*20mm*3.14 (since May-2026).
G-band normal image: I_vls_open = Is * (25*25*3.14) * 0.026 * 0.4932
⇒[correction]⇒ G-band normal image:
I_vls_open = Is * (20*20*3.14) *
0.020 * 0.4932
Stray light component: I_vls_close = Is * (open area) * 0.4932
VLS_open image : [normal G-band image] overlapped with [stray light image]
VLS_close image : [stray light image] only.
[Total intensity of VLS_open image] = 1.0820e+11 (DN/sec)
[Total intensity of VLS_close image] = 4.8259e+10 (DN/sec)
[Total intensity of normal G-band image] = 5.9941e+10 (DN/sec)
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Ratio of total image intensity : [VLS_close]/[VLS_open] = 4.8259e+10/1.0820e+11 = 0.446 [stray light comp.]/[norm. G-band] = 4.8259/5.9941 = 0.8051 |
[open area ratio] = [open area (mm^2)]/[XRT effective area (228 mm^2)]
[open area ratio] = [4.826e10 * 0.00026 * 1963.5] / [228 * 5.994e10] = 0.001802
[open area ratio] ⇒ [4.826e10 *
0.00020 * 1963.5] / [228 * 5.994e10] = 0.001386 (applied since 10-Nov-2025)
[open area ratio] ⇒ [4.826e10 *
0.00020 * 1256.6] / [228 * 5.994e10] = 0.0008875 (applied since 31-May-2026)
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Ratio of total image intensity : [VLS_close]/[VLS_open] = 1.0767e12/1.1295e12 = 0.953.. [stray light comp.]/[norm. G-band] = 1.0767e12/5.2812e10 = 20.4 |
[open area ratio] = [1.077e12 * 0.00026 * 1963.5] / [228 * 5.281e10] = 0.04566
[open area ratio] ⇒ [1.077e12 *
0.00020 * 1963.5] / [228 * 5.281e10] = 0.03513 (applied since 10-Nov-2025)
[open area ratio] ⇒ [1.077e12 *
0.00020 * 1256.6] / [228 * 5.281e10] = 0.02248 (applied since 31-May-2026)