Emulsion GEM common exposure test beam results Annarita

Emulsion – GEM common exposure test beam results Annarita Buonaura, Valeri Tioukov On behalf of Napoli emulsion group This activity was supported by AIDA 2020 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 1

Test Beam Summary • At the SPS – H 4 (Oct 2015): • Matching between emulsions and GEM • CS (emulsion doublets), ECC and CES were exposed together with GEM at different angles and magnetic field • In collaboration with Frascati GEM group GEM installed Inside Goliath magnet at East Area (SPS) CS attached to GEM 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 2

Emulsion Films • Emulsion films produced in Nagoya University • Film dimensions • Surface: 125 mm x 100 mm • Total thickness: 290 μm • Emulsion Layer: 60 μm • Plastic Base: polystyrene : 170 μm • New emulsion gel developed in Nagoya University • Grain density: 50 grains/100 μm (higher than OPERA films) • Emulsion production • Emulsion poured in middle August 2015 and cut by hand • Shipped to CERN by plane • Total amount of emulsion films produced: 120 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 3

Exposures Summary Setups: 1. 2 emulsion doublets (CS) attached on GEM upstream and downstream surfaces in magnetic field Low density: 50 tracks/cm 2/angle Beam Exposure 1 (CS 3 + CS 4) Target: 2 x CS Magnetic Field: - 1 T Exposure 2 (CS 5 + CS 6) Beam Front view Beam Target: 2 x CS Magnetic Field: +1 T Back view 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 4

Exposures Summary Setups: 1. 2 emulsion doublets (CS) attached on GEM upstream and downstream surfaces in magnetic field 2. 1 CS doublet attached on GEM upstream surface without magnetic field coupled with a Compact Emulsion Spectrometer Exposure 2 (CS 7) Target: 1 x CS + 1 x CES B=0 T Magnetic Field: 0 T -30° 0° 7. 5° 15° 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 30° 45° 5

Matching procedure 1. Track reconstruction in emulsions • Scanning of an area of 10 x 8 cm 2 on each emulsion layer in the Napoli Emulsion Laboratory. • Reconstruction of track segments in each emulsion film. • Alignment between the two emulsion films constituting each CS and subsequent track reconstruction 8 cm XY distribution of reconstructed tracks in a CS doublet Slope distribution of reconstructed tracks in a CS doublet 15° peak 7. 5° peak 0° peak 10 cm 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 6

Matching procedure 1. Track reconstruction in emulsions 2. For each peak: hit reconstruction in GEM performed by Frascati group XY distribution of reconstructed hits in GEM at peak 0° 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 7

Matching procedure 1. Track reconstruction in emulsions 2. For each peak: hit reconstruction in GEM performed by Frascati group 3. Alignment between CS doublets and GEM • Pattern matching performed peak by peak • Offset range in XY: +-10 mm • Angular range: -0. 08, +0. 08 rad Peaks of coincidences between CS 3 and GEM: 0° 7. 5° 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 15° 8

Matching procedure 1. 2. 3. 4. Track reconstruction in emulsions For each peak: hit reconstruction in GEM performed by Frascati group Alignment between CS doublets and GEM Track reconstruction in the system CS+GEM • Performed peak by peak XY distribution of reconstructed tracks in a CS + GEM (0° peak) Slope distribution of reconstructed tracks in a CS + GEM (0° peak) 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 9

Matching results • For each angular peak evaluated the variance between the position of the track in the CS doublet and the position of the corresponding hit on the GEM detector • B field is along the x direction so we expect to see its effects on the y direction Variance for the couple CS 3 + GEM (peak 0°) 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 10

Matching results 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 11

Matching results CS 3_GEM CS 5_GEM CS 7_GEM θ = 0° B = 0 T σx σy 77± 2 52± 1 73± 2 57± 1 105± 13 78± 20 θ = 7. 5° B = -1 T θ = 7. 5° B = 0 T σx σy 108± 7 221± 13 76± 2 132± 6 98± 10 154± 15 θ = 15° B = -1 T θ = 15° B = 0 T σx σy 110± 6 369± 36 72± 2 63± 2 98± 14 218± 17 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 12

Conclusions • Performed for the first time the match between emulsion and GEM detectors. • Analysis has been performed for run at angle: 0°, 7. 5° and 15° for exposures both with and without magnetic field and resolution on GEM position has been evaluated in all the different conditions. PERSPECTIVES • Perform the analysis also with runs at larger angles: 30° and 45° • Improved the matching by taking advantage of the reconstruction of GEM hits in micro-TPC mode 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 13

Test-beam in summer 2016 modified CES study Rohacell solution for CES was tested in 2015. We confirmed thath the local resolution is fine but on the bigger scale observed some planarity problems. Using this solution is difficult to maintain gap stability with the accuracy better then 0. 2 mm. Frame solution to be tested – we use precise rigid frames with a thing film (mylar) stretched over as a mechanical support for the emulsion. This guarantee flatness and it’s also more lightweight solution in respect to the Rohacell – factor of 5 less material (10 mg/cm 2/cell instead of 50 mg/cm 2/cell) 8 th SHi. P Collaboration Meeting - London 13 -15/06/2016 14