Canada’s National Laboratory for Particle and Nuclear Physics Laboratoire national canadien pour la recherche en physique nucléaire et en physique des particules

Casting Light on Antimatter: ALPHA Antihydrogen Experiment at CERN TRIUMF FIVE YEAR PLAN: INT’L PEER REVIEW NOV 14, 2013

Makoto C. Fujiwara ALPHA-Canada PI Research Scientist

TRIUMF Owned and operated as a joint venture by a consortium of Canadian universities via a contribution through the National Research Council Canada Propriété d’un consortium d’universités canadiennes, géré en co-entreprise à partir d’une contribution administrée par le Conseil national de recherches Canada

Antihydrogen Atom

Pbar = antiproton Hbar = antihydrogen, anit-H (bound state of pbar and e+)

Outline • Motivations: “Big Picture” • ALPHA experiment • Recent achievements – Trapping, Microwaves, ALPHA-2 construction

• Prospects for next five years – Precision spectroscopy – Gravity

• Summary

Makoto Fujiwara, ALPHA

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Motivations (experimental) Atomic hydrogen: • 75% of visible universe; one of best studied systems – 1s-2s level: 2 466 061 413 187 035 (10) Hz Δf/f~10-15 – Hyperfine splitting: 1 420 405 751.768 (1) Hz 10-12

Antihydrogen (anti-H): produced in large quantities by ATHENA, ATRAP (2002) • Comparison of H and anti-H: “Textbook” experiment! – Compelling regardless of theoretical motivations

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Big Picture • What is Particle Physics?

(Grossman)

• “Simple answer”: The SM, including Higgs, works extremely well! • Many open issues, in particular: – Naturalness of Higgs mass & Cosmological constant – Require fine-tuning by O(30), O(120)? – Hopefully, LHC & low energy expt’s will solve them!

• “L=?” really the right question to ask? Is (effective) Quantum Field Theory correct description of Nature? 5

Antihydrogen Motivations • Test of CPT – CPT is a fundamental property of local, relativistic Quantum Field Theory – Assuming: Unitarity, Spin Statistics, Lorentz Invariance etc., CPT theorem demands atomic spectrum of H and Anti-H be identical – Violation of CPT would force radical change in theory, incl. validity of QFT – Such probability is low!

• Matter-Antimatter Asymmetry in the Universe – CPT violation may be responsible (c.f. Sakharov Condition)

• Test of gravity (not in the SM) in regimes previously untested Makoto Fujiwara, ALPHA

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ALPHA: Antihydrogen Trapping Apparatus U. Calgary joined TRIUMF consortium as Associate Member

ALPHA • •

16 institutions ~40 physicists

ALPHA-Canada • • • • •

5 Canadian institutions More than 1/3 of ALPHA (single largest group) 10 Faculty/Scientists 6 grad students Leadership in detection, microwave spectroscopy, lase cooling

TRIUMF •

Makoto Fujiwara, ALPHA

Fujiwara, Olin, Gill (Olchanski, Kurchaninov) + Many Technical people 7

ALPHA Experiment Animation

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Antihydrogen Trapped (for 172 ms) Letter to Nature, Nov. 17, 2010

ALPHA-Canada 15 out of 42 authors (incl. 5 students)

Among top news stories in 2010 – #1 Physics Breakthrough: PhysicsWorld – #1 Most read news: Nature – #2 Science News: CBC National Makoto Fujiwara, ALPHA

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Example of HQP role: Richard Hydomako (Calgary) Transporting $0.5M magnet

Richard Hydomako, U. Calgary (responsible for detector analysis) 2011 Thesis Prize Div. Nuclear Phys. Canadian Association of Physicists

Ph.D. thesis published in “Best of best” Thesis Series Springer

Confinement of Antihydrogen for 1000 s

• Increased trapping rates by x5 (hard to tweak zero) • Trapping time increased by x5000 • “Game changer” Cover, Nature Physics, July 2011 Issue Principle author: Fujiwara (TRIUMF)

– Opens up many possibilities

• Detailed studies of dynamics 11

First Spectroscopy on Antihydrogen Atoms Canadian-Lead Initiative: Walter Hardy (UBC), Mike Hayden (SFU) M. Ashkezari (SFU), T. Friesen (Calgary) S. Stracka, D. Gill, A. Olin MCF (TRIUMF)

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Microwave-induced Positron Spin Resonance (PSR)

Installation at CERN, July 2011

– Developed at SFU/UBC/TRIUMF – Trap ~1 Anti-H/20 min – Irradiate with mW • Drive transition: trapped  un-trapped • Look for annihilations – Multivariate (blind) analysis • improved S/N by x10

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It worked! Big Relief! Letter to Nature, March 2012 Principal author: Michael Hayden (SFU)

• First spectroscopic measurements on anti-H!!! – Precision limited: O(10-3) – Demonstrates it’s possible to do spectroscopy on a single anti-atom at a time – “Historic!” – Nature Editor – Annihilation detection: key – Major Canadian-led success

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Precision Spectroscopy with ALPHA-2

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2012-: ALPHA-2 Construction

• New apparatus for laser and microwave spectroscopy • Very complex design & construction job for cryostat • Unique TRIUMF contributions – Cryo-engineering – Precision welding – Canadian industry (PAVAC) – >3000 hours of machining at TRIUMF and Calgary

CERN Bulletin November, 2012

Canadian contribution recognized! Makoto Fujiwara, ALPHA

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Precision Laser Spectroscopy with ALPHA-2 “Hänsch Plot”

1s-2s two-photon spectroscopy

• Doppler effect cancels • High precision in matter sector • “Lamp post” Makoto Fujiwara

High Precision NMR of Antihydrogen

Ashkezari (SFU), Friesen (Calgary), Evetts (UBC): Hayden, Hardy

• Nuclear Magnetic Resonance – – – –

Antiproton spin flip Broad maximum at 0.65 T Insensitive B field homogeneity! Initially at few kHz (~10-6) 