Beam paths to HTD (miniCBM)

(return)

Introduction

Cave D is shares most of the beam paths with cave C. During the shutdown 2017-2018 the beamline has been modified to host CBM beam test facility (mini-CBM). The modification is mainly modification of the position of the switching magnet HTDMU1 in order to be able to deflect higher-rigidity beam towards the target. The beams requested are maximum rigidity (18.66 Tm with respect to 10 Tm before the modification). Summary of the modification (courtesy Ch. Sturm):

Presentation: Sturm_20180220-BeamRetreat-mCBM-CSturm-v7.pdf

The contact persons are: Christian Sturm and David Emschermann.

Beams

The expected beams are:

Optics

Currently one beam path is considered:

• SIS18_TH_HTD

For this beam path there are 3 available settings: STANDARD, LEGACY and ENGRUN2018.

SIS18_TH_HTD_STANDARD

Standard optics is characterized by very large optics functions at the end of the beamline. A comparison of original optics in MIRKO and its reproduction in MADX:

Here are the optics files. Note that original MIRKO file contains GTHDKY1 kicker (actually clled HTCKY1 by mistake), which is not there anymore, so it was removed from LSA files. This optics, especially in the final part of it, must be reworked to adapt to miniCBM target position. This work is ongoing, but for the Dry Runs old optics is used.

SIS18_TH_HTD_LEGACY

The mi-file originally did not exist. It was created from sisthhtc.mi file by removing HTCKY1, HTCKY2, HTCKX2, HTCQT21, HTCQT22, HTCQT23 and adding GHTDMU1 with bending angle of +0.139626

The beta functions are:

SIS18_TH_HTD_ENGRUN2018

Optics optimized during Engineering Run 2018.

The beta functions are:

Images and Photos

miniCBM layout:

mini-CBM target (courtesy David Emschermann):