MADMAX: introduction and status Chang Lee on behalf of the MADMAX - PowerPoint PPT Presentation

MADMAX: introduction and status Chang Lee on behalf of the MADMAX collaboration MPI for Physics 3rd Workshop on Microwave cavities and detectors for Axion Research Aug 24th, Livermore, CA, USA � 1

MADMAX : Introduction and status C. Lee Post-inflation axion Our Our Universe: Universe m a < 10 meV PQ symmetry breaking after inflation m a ~ 100 μ eV 3 rd Workshop on Microwave cavities and detectors for Axion Research � 2

MADMAX : Introduction and status C. Lee High-mass challenge preferred by 
 post-inflation scenarios • 40—400 μ eV (10—100 GHz): 
 Challenging for traditional resonant cavity 
 due to smaller volume, lower Q 3 rd Workshop on Microwave cavities and detectors for Axion Research � 3

MADMAX : Introduction and status C. Lee Axion signal • Inverse-Primako ff in matter g a γ B e E a = − a ε B e A. J. Millar et al JCAP01(2017)061 B e • Discontinuity of ε or B e E γ Region 1 Region 2 generates propagating EM 2 e 1 = 4 e 2 = 1 g E 2 field. E γ 1 k 1 k 2 g g H 2 H 1 H ∥ ,1 = H ∥ ,2 E ∥ ,1 = E ∥ ,2 E a y g E 1 2 a a E 1 E 2 x E a z 1 B e 3 rd Workshop on Microwave cavities and detectors for Axion Research � 4


 
 
 MADMAX : Introduction and status C. Lee signal power • Simplest: a metallic mirror ( ε = ∞ ) 
 E 0 = 1.3 × 10 − 12 [ V / m ] × ( B e 10 T ) ~12 photons / day / m 2 (@ 25 GHz) n = 5 • Mirror + dielectric: 
 Q ∝ ε Leaky resonator, 
 β = E / E 0 β ~10 boost factor: 
 P ∝ E 2 ∝ β 2 standing propagating • Add more dielectric disks… wave wave = λ 4 n 3 rd Workshop on Microwave cavities and detectors for Axion Research � 5

MADMAX : Introduction and status C. Lee Dielectric haloscope B e • more sources + 
 coherent interferences • Boost Mirror Dielectric Disks Receiver more N! β 2 ν 3 rd Workshop on Microwave cavities and detectors for Axion Research � 6

MADMAX : Introduction and status C. Lee Boost 80 discs LnAlO 3 Δ ν ν = 2 × 10 − 3 • β 2 > 60,000 possible 
 50 MHz with ~80 disks. 
 • Disk spacings tune β . • Broad band for coverage • higher β for confirmation 3 rd Workshop on Microwave cavities and detectors for Axion Research � 7

MADMAX : Introduction and status C. Lee Scan strategy • Area Law: 
 same area P sig x Δν is independent of disk spacings. Δ ν = ( k B T sys t scan 2 2 S N ) ( P sig ) • 0 , β 2 , n , A , N , 1 P sig ∝ B 2 140 Δ ν 120 • Narrower peak leads 100 to faster scan. 80 60 40 • In practice, 
 20 t tot_adj ≈ t tot_scan . 0 24.8 25.0 25.2 25.4 25.6 3 rd Workshop on Microwave cavities and detectors for Axion Research � 8

MADMAX : Introduction and status C. Lee collaboration MA gnetized D isk-and- M irror A xion e X periment DESY, Univ. of Hamburg, CEA-IRFU, MPI for Radioastronomy, 
 RWTH Aachen, Univ. of Zaragoza, MPI for Physics 3 rd Workshop on Microwave cavities and detectors for Axion Research � 9

MADMAX : Introduction and status C. Lee Instrument mirror 4K Cover the QCD axion @ 10—100 GHz 3 rd Workshop on Microwave cavities and detectors for Axion Research � 10

MADMAX : Introduction and status C. Lee Simulation • Maxwell-Axion equation solved by analytic, FEM, ray tracing, and other methods. dielectric 
 disk • 1D calculations confirmed. • Latest topics: 
 3D e ff ects, boundary loss, di ff raction 3 rd Workshop on Microwave cavities and detectors for Axion Research � 11

MADMAX : Introduction and status C. Lee Boost 5 disks measurement • Boost factor is indirectly confirmed by the reflectivity and group delay measurements. measurement 
 by S. Knirck & J. Egge Reflectivity Group delay [ns] 0.3 4.5 Reflectivity Measurement Reflectivity Simulation 4 Group Delay Measured 0.25 Group Delay Simulated 80 discs 3.5 1 3 0.2 2.5 Boost Factor 0.15 2 Re fl ectivity 1.5 0.5 0.1 Group Delay 1 (scaled) 0.5 0.05 0 0 0 -0.5 14 16 18 20 22 24 Frequency [GHz] 3 rd Workshop on Microwave cavities and detectors for Axion Research � 12

MADMAX : Introduction and status C. Lee receiver chain FFT (signal generator) • 10 -23 W detected in a week 3 rd Workshop on Microwave cavities and detectors for Axion Research � 13

MADMAX : Introduction and status C. Lee System temperature • Thermal emissivity of the internal parts to be measured. 
 goal: Δ T < 0.5 K • Bottleneck: ~5 K noise temperature from HEMT • Quantum noise: 
 ~0.48K @ 20 GHz t scan Δ ν ∝ T 2 sys , T sys = T bg + T amp • Latest options 
 < 4K 5~6K (JPA, TWPA, …) to be considered 3 rd Workshop on Microwave cavities and detectors for Axion Research � 14

MADMAX : Introduction and status C. Lee Mechanical design • Baseline design by 
 M. Matysek & D. Kittlinger • 80 disks at cryogenic temp. image by M. Matysek • Each moves 1.5—30mm w/ 
 < 60 μ m precision for β ~1000. • Piezo motor for moving disks • test @ cryogenic 
 + high magnetic field • Hysteresis, accuracy measurement at varying loads μ m 3 rd Workshop on Microwave cavities and detectors for Axion Research � 15

MADMAX : Introduction and status C. Lee Dielectric study dielectrics ε = n 2 tan δ β max = 2 n − 1 n Al 2 O 3 10 10 -5 for 1 mirror + 1 disk setup LaAlO 3 24 3 x 10 -5 at resonance TiO 2 100 3 x 10 -5 single 
 crystal 1 Sapphire + mirror 3 rd Workshop on Microwave cavities and detectors for Axion Research � 16

MADMAX : Introduction and status C. Lee Magnets CEA Saclay • Prototype magnets for R&D (2~3 years) • 3-4 T, ~400mm bore • Used magnets at Saclay under survey. • Final setup (> 5 years) Preliminary • 10T dipole, B 2 A: ~100 T 2 m 2 , 
 ~400 MJ stored in 2m x 1m 2 • Two independent design studies 
 by CEA Saclay & Bilfinger Noell GmbH Noell Bilfinger 3 rd Workshop on Microwave cavities and detectors for Axion Research � 17

MADMAX : Introduction and status C. Lee Site & infrastructure • DESY o ff ered 
 HERA north hall (H1) • Large supply of LHe for magnets • Support for magnets’ weight (~150 tons) image from http://h1.desy.de 3 rd Workshop on Microwave cavities and detectors for Axion Research � 18

MADMAX : Introduction and status C. Lee Prototype • Feasibility test & First scientific data • starts in ~3 yrs 20 x Φ 30 cm disks Mirror + motors Preliminary design 3~4 T 3 rd Workshop on Microwave cavities and detectors for Axion Research � 19

MADMAX : Introduction and status C. Lee Future perspective Prototype Full scale: 80 x 1m 2 disks, 
 10T magnet in 202x? 3 rd Workshop on Microwave cavities and detectors for Axion Research � 20

MADMAX : Introduction and status C. Lee Summary • 40—400 μ eV is an interesting target for post- inflation QCD axion search. • Dielectric haloscope is a promising technique. • MADMAX is developing, aiming to cover the parameter space. • PRL 118 091801 
 JCAP01 (2017) 061 
 MADMAX white paper 3 rd Workshop on Microwave cavities and detectors for Axion Research � 21

MADMAX: Introduction and status C. Lee Back-up slides 3 rd Workshop on Microwave cavities and detectors for Axion Research

MADMAX : Introduction and status C. Lee Boost mirror disk • Disks + mirror boosts signal by β = E / E 0 • Transparent mode: 
 A. J. Millar et al JCAP01(2017)061 δ = n x d x ν = π , 3 π , 5 π … 
 constructive interference. • Resonant mode: 
 δ = π /2, 3 π /2, … 
 disks + mirror forms a leaky resonator. • Combined boost from both contributions. 3 rd Workshop on Microwave cavities and detectors for Axion Research � 23

MADMAX : Introduction and status C. Lee Transfer matrix • Transfer matrix formalism w/ boundary conditions E ∥ ,1 = E ∥ ,2 H ∥ ,1 = H ∥ ,2 A. J. Millar et al JCAP01(2017)061 3 rd Workshop on Microwave cavities and detectors for Axion Research � 24

MADMAX : Introduction and status C. Lee list of show-stoppers • Unexpected losses • High tan δ , tilt, 3D loss, di ff raction • Components incompatible with high B field Incident Wave • Mechanical precision too di ffi cult. Re fl ected / Transmitted Wave 3 rd Workshop on Microwave cavities and detectors for Axion Research � 25

MADMAX : Introduction and status C. Lee Dielectric width • For a set of dielectric disk with width d, how wide frequency can we cover? • 1mm 15—30GHz • 3mm 5—15GHz (LaAlO3) 3 rd Workshop on Microwave cavities and detectors for Axion Research � 26

MADMAX : Introduction and status C. Lee Fine-tuning search 3 rd Workshop on Microwave cavities and detectors for Axion Research � 27