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Configurations for Special Runs / VdM in 2026 (under constructions: for now the same as 2025 vdM!!!) |
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This page reflects the planned program in 2025. The times for scans are not updated after data-taking but some are based on previous years as indicated. In case of doubts do not hesitate to contact the LPC (or in case inconsistencies/mistakes are spotted).
| Step | Duration | Experiments activities | Remarks | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Scans IP2/8 - VdM optics |
~10h |
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Filling Scheme: Scans should ideally happen in the same fill. If beams are dumped during a scan will need to repeat at least that full part LHCb VELO Ghost charge measurements throughout ALICE scan, if possible. Estimated times. |
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| LSCS and Scans IP1/5 - VdM optics (50m at IP8) |
~24h |
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Filling Scheme: LSC and scans should ideally happen in the same fill. If beams are dump during a scan will need to repeat at least that full part LHCb VELO Ghost charge measurements during the vdM scans, if possible. Times have been revisited for 2026. |
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| Items | Remarks |
|---|---|
| Filling Scheme | 525ns_140b_140_75_16_8bpi_19inj_800ns_bs525ns Download |
| Bunch Spacing | 525 ns (minimal) |
| Injections | up to 2 batches of 4 bunches |
| Emittance in Stable Beams | as during physics fills |
| Intensity in Stable Beams | around 1.4x1011 ppb |
| Brightness (bunch intensity / emittance) | as during physics fills |
| Items | Remarks |
|---|---|
| Filling Scheme | 525ns_146b_144_35_20_8bpi_21inj_800ns_bs525ns Download |
| Bunch Spacing | 525 ns (minimal) |
| Injections | up to 2 batches of 4 bunches |
| Emittance in Stable Beams | 3µm -- tolerable variations: 2.5µm to 3.5µm; some spread O(20%-30%) is welcome |
| Intensity in Stable Beams | 0.8x1011 ppb -- tolerable variations: 0.7x1011 ppb to 0.9x1011 ppb; some spread O(20%-30%) is welcome |
| Profiles | Preparation for VdM : Gaussian profiles which factorise the beam wrt H and V planes |
| Injection Optics | With crossing angle to not have problems with LR interactions when beams are large at injection |
| Items | Remarks |
|---|---|
| Filling Scheme | Multi_74b_63_34_29_4bpi_23inj_1000ns_bs1000ns Download |
| Bunch Spacing | 1000 ns (minimal) |
| Injections | up to 4 batches of 1 bunch ("traditional" VdM schemes) |
| Emittance in Stable Beams | 3µm for LHCb; >3µm for ALICE (second in scan programme) |
| Intensity in Stable Beams | 0.7x1011 - 0.9x1011 ppb in LHCb 0.4x1011 - 0.9x1011 ppb in ALICE (ALICE is second in the scan programme) |
| Profiles | Preparation for VdM : Gaussian profiles which factorise the beam wrt H and V planes |
| IP8 beta* | 24m in IP2/8 scan, 50m in IP1/5 scan |
| IP8 Dipole polarity | Down, + |
| IP8 external half crossing angle | -300 µrad; internal half crossing angle : -138 µrad --> effective half crossing angle at IP: -438 µrad. |
| IP2 beta* | 19m |
| IP2 polarities | + / + (Dipole and L3 magnet) |
| IP2 internal crossing angle | -72µrad |
| IP2 external crossing angle | 145 µrad |
| IP2 effective crossing angle | +73µrad which is ok for using the ZDC |
| IP2 special request | BRANs retracted |
| Injection Optics | With crossing angle to not have problems with LR interactions when beams are large at injection |