Editing Antimatter (section)

==Artificial production==

===Positrons===
{{Main|Positron}}

Positrons were reported<ref>
{{cite press release
 |publisher=[[Lawrence Livermore National Laboratory]]
 |date=3 November 2008
 |title=Billions of particles of anti-matter created in laboratory
 |url=https://phys.org/news/2008-11-billions-particles-anti-matter-laboratory.html
 |archive-url=https://web.archive.org/web/20151206012202/http://phys.org/news/2008-11-billions-particles-anti-matter-laboratory.html
 |url-status=dead
 |archive-date=6 December 2015
 |access-date=19 November 2008
}}</ref> in November 2008 to have been generated by [[Lawrence Livermore National Laboratory]] in large numbers. A [[laser]] drove [[electrons]] through a [[gold]] target's [[atomic nucleus|nuclei]], which caused the incoming electrons to emit [[energy]] [[quantum|quanta]] that decayed into both matter and antimatter. Positrons were detected at a higher rate and in greater density than ever previously detected in a laboratory. Previous experiments made smaller quantities of positrons using lasers and paper-thin targets; newer simulations showed that short bursts of ultra-intense lasers and millimeter-thick gold are a far more effective source.<ref>
{{cite magazine
 |date=19 November 2008
 |title=Laser creates billions of antimatter particles
 |url=http://www.cosmosmagazine.com/news/2345/laser-creates-billions-particles-antimatter
 |magazine=[[Cosmos Magazine]]
 |access-date=1 July 2009
 |archive-url=https://web.archive.org/web/20090522151227/http://www.cosmosmagazine.com/news/2345/laser-creates-billions-particles-antimatter
 |archive-date=22 May 2009
 |url-status=live
}}</ref>

In 2023, the production of the first electron-positron beam-plasma was reported by a collaboration led by researchers at [[University of Oxford]] working with the [[High-Radiation to Materials]] (HRMT)<ref>{{Cite journal |last1=Efthymiopoulos |first1=I |last2=Hessler |first2=C |last3=Gaillard |first3=H |last4=Grenier |first4=D |last5=Meddahi |first5=M |last6=Trilhe |first6=P |last7=Pardons |first7=A |last8=Theis |first8=C |last9=Charitonidis |first9=N |last10=Evrard |first10=S |last11=Vincke |first11=H |last12=Lazzaroni |first12=M |date=2011|journal = 2nd International Particle Accelerator Conference |title=HiRadMat: A New Irradiation Facility for Material Testing at CERN |url=https://cds.cern.ch/record/1403043}}</ref> facility at [[CERN]].<ref name=":0">{{Cite journal |last1=Arrowsmith |first1=C. D. |last2=Simon |first2=P. |last3=Bilbao |first3=P. J. |last4=Bott |first4=A. F. A. |last5=Burger |first5=S. |last6=Chen |first6=H. |last7=Cruz |first7=F. D. |last8=Davenne |first8=T. |last9=Efthymiopoulos |first9=I. |last10=Froula |first10=D. H. |last11=Goillot |first11=A. |last12=Gudmundsson |first12=J. T. |last13=Haberberger |first13=D. |last14=Halliday |first14=J. W. D. |last15=Hodge |first15=T. |date=2024-06-12 |title=Laboratory realization of relativistic pair-plasma beams |journal=Nature Communications |language=en |volume=15 |issue=1 |pages=5029 |doi=10.1038/s41467-024-49346-2 |pmid=38866733 |pmc=11169600 |issn=2041-1723|arxiv=2312.05244 |bibcode=2024NatCo..15.5029A }}</ref> The beam demonstrated the highest positron yield achieved so far in a laboratory setting. The experiment employed the 440 GeV proton beam, with <math>3\times 10^{11}</math> protons, from the [[Super Proton Synchrotron]], and irradiated a particle converter composed of [[carbon]] and [[tantalum]]. This yielded a total <math>1.5\times 10^{13}</math> electron-positron pairs via a [[particle shower]] process. The produced pair beams have a volume that fills multiple [[Debye length|Debye spheres]] and are thus able to sustain collective plasma oscillations.<ref name=":0" />

===Antiprotons, antineutrons, and antinuclei===
{{Main|Antiproton|Antineutron}}

The existence of the antiproton was experimentally confirmed in 1955 by [[University of California, Berkeley]] [[physicist]]s [[Emilio Segrè]] and [[Owen Chamberlain]], for which they were awarded the 1959 [[Nobel Prize in Physics]].<ref>{{cite web | url=http://nobelprize.org/nobel_prizes/physics/laureates/ | title=All Nobel Prizes in Physics | archive-url=https://web.archive.org/web/20100723052215/http://nobelprize.org/nobel_prizes/physics/laureates/ | archive-date=23 July 2010 | url-status=live}}</ref> An antiproton consists of two up antiquarks and one down antiquark ({{Subatomic particle|link=yes|Up antiquark}}{{Subatomic particle|link=yes|Up antiquark}}{{Subatomic particle|link=yes|Down antiquark}}). The properties of the antiproton that have been measured all match the corresponding properties of the proton, with the exception of the antiproton having opposite electric charge and magnetic moment from the proton. Shortly afterwards, in 1956, the antineutron was discovered in proton–proton collisions at the [[Bevatron]] ([[Lawrence Berkeley National Laboratory]]) by [[Bruce Cork]] and colleagues.<ref>{{cite web | url=http://bancroft.berkeley.edu/Exhibits/physics/extending02.html | title=Breaking Through: A Century of Physics at Berkeley, 1868–1968 | publisher=[[Regents of the University of California]] | date=2006 | access-date=18 November 2010 | archive-url=https://web.archive.org/web/20100709235643/http://bancroft.berkeley.edu/Exhibits/physics/extending02.html | archive-date=9 July 2010 | url-status=live}}</ref>

In addition to anti[[baryon]]s, anti-nuclei consisting of multiple bound antiprotons and antineutrons have been created. These are typically produced at energies far too high to form antimatter atoms (with bound positrons in place of electrons). In 1965, a group of researchers led by [[Antonino Zichichi]] reported production of nuclei of [[antideuterium]] at the Proton Synchrotron at [[CERN]].<ref>{{cite journal | bibcode=1965NCimS..39...10M | title=Experimental observation of antideuteron production | date=1965 | last1=Massam | first1=T. | last2=Muller | first2=Th. | last3=Righini | first3=B. | last4=Schneegans | first4=M. | last5=Zichichi | first5=A. | journal=Il Nuovo Cimento | volume=39 | issue=1 | pages=10–14 | doi=10.1007/BF02814251| s2cid=122952224 }}</ref> At roughly the same time, observations of antideuterium nuclei were reported by a group of American physicists at the Alternating Gradient Synchrotron at [[Brookhaven National Laboratory]].<ref>{{cite journal | bibcode=1965PhRvL..14.1003D | date=June 1965 | first1=D. E | last1=Dorfan | title=Observation of Antideuterons | last2=Eades | first2=J. | last3=Lederman | first3=L. M. | last4=Lee | first4=W. | last5=Ting | first5=C. C. | journal=Physical Review Letters | volume=14 | issue=24 | pages=1003–1006 | doi=10.1103/PhysRevLett.14.1003}}</ref>

===Antihydrogen atoms===
{{Main|Antihydrogen}}
<!-- Should antihelium be folded into this section? I haven't checked to see whether they'd created antihelium nuclei or true antihelium atoms with bound positrons. -->
{{Antimatter_facilities}}
In 1995, [[CERN]] announced that it had successfully brought into existence nine hot antihydrogen atoms by implementing the [[SLAC]]/[[Fermilab]] concept during the [[PS210 experiment]]. The experiment was performed using the [[Low Energy Antiproton Ring]] (LEAR), and was led by Walter Oelert and Mario Macri.<ref>{{Cite web
 |last=Gabrielse
 |first=Gerald
 |display-authors=etal
 |collaboration=ATRAP Collaboration
 |year=1996
 |title=The production and study of cold antihydrogen
 |url=https://cds.cern.ch/record/299823/files/B00006161.pdf
 |pages=1–21
 |publisher=CERN
 |id=No. SPSLC-I-211
 |access-date=22 August 2018
 |archive-date=25 March 2020
 |archive-url=https://web.archive.org/web/20200325005019/https://cds.cern.ch/record/299823/files/B00006161.pdf
 |url-status=live
 }}</ref> Fermilab soon confirmed the CERN findings by producing approximately 100 antihydrogen atoms at their facilities. The antihydrogen atoms created during PS210 and subsequent experiments (at both CERN and Fermilab) were extremely energetic and were not well suited to study. To resolve this hurdle, and to gain a better understanding of antihydrogen, two collaborations were formed in the late 1990s, namely, [[ATHENA]] and [[ATRAP]].

In 1999, CERN activated the [[Antiproton Decelerator]], a device capable of decelerating antiprotons from {{val|3.5|ul=GeV}} to {{val|5.3|u=MeV}}&nbsp;– still too "hot" to produce study-effective antihydrogen, but a huge leap forward. In late 2002 the ATHENA project announced that they had created the world's first "cold" antihydrogen.<ref>{{cite journal
 |last=Amoretti
 |first=M.
 |display-authors=etal
 |date=2002
 |title=Production and detection of cold antihydrogen atoms
 |url=https://cds.cern.ch/record/581488
 |journal=[[Nature (journal)|Nature]]
 |volume=419
 |issue=6906
 |pages=456–459
 |bibcode=2002Natur.419..456A
 |doi=10.1038/nature01096
 |pmid=12368849
 |s2cid=4315273
 |access-date=30 August 2017
 |archive-date=23 March 2020
 |archive-url=https://web.archive.org/web/20200323082118/https://cds.cern.ch/record/581488
 |url-status=live
 |doi-access=free
 }}</ref> The ATRAP project released similar results very shortly thereafter.<ref>{{cite journal
 |last=Gabrielse
 |first=G.
 |display-authors=etal
 |date=2002
 |title=Background-free observation of cold antihydrogen with field ionization analysis of its states
 |url=https://cds.cern.ch/record/977774
 |journal=[[Physical Review Letters]]
 |volume=89
 |issue=21
 |page=213401
 |bibcode=2002PhRvL..89u3401G
 |doi=10.1103/PhysRevLett.89.213401
 |pmid=12443407
 |access-date=30 August 2017
 |archive-date=23 March 2020
 |archive-url=https://web.archive.org/web/20200323082107/https://cds.cern.ch/record/977774
 |url-status=live
 }}</ref> The antiprotons used in these experiments were cooled by decelerating them with the Antiproton Decelerator, passing them through a thin sheet of foil, and finally capturing them in a [[Penning-Malmberg trap|Penning–Malmberg trap]].<ref>
{{cite journal
 |last1=Malmberg |first1=J. H.
 |last2=deGrassie |first2=J. S.
 |date=1975
 |title=Properties of a nonneutral plasma
 |journal=[[Physical Review Letters]]
 |volume=35 |issue=9 |pages=577–580
 |bibcode=1975PhRvL..35..577M
 |doi=10.1103/PhysRevLett.35.577
}}</ref> The overall cooling process is workable, but highly inefficient; approximately 25&nbsp;million antiprotons leave the Antiproton Decelerator and roughly 25,000 make it to the Penning–Malmberg trap, which is about {{sfrac|1|1000}} or 0.1% of the original amount.

The antiprotons are still hot when initially trapped. To cool them further, they are mixed into an electron plasma. The electrons in this plasma cool via cyclotron radiation, and then sympathetically cool the antiprotons via [[Coulomb potential|Coulomb]] collisions. Eventually, the electrons are removed by the application of short-duration electric fields, leaving the antiprotons with energies less than {{val|100|u=[[Electronvolt|meV]]}}.<ref>
{{cite journal
 |last=Gabrielse |first=G.
 |display-authors=etal
 |date=1989
 |title=Cooling and slowing of trapped antiprotons below 100 meV
 |journal=[[Physical Review Letters]]
 |volume=63 |issue=13 |pages=1360–1363
 |bibcode=1989PhRvL..63.1360G
 |doi=10.1103/PhysRevLett.63.1360
 |pmid=10040547
 }}</ref> While the antiprotons are being cooled in the first trap, a small cloud of positrons is captured from [[radioactive]] [[sodium]] in a Surko-style positron accumulator.<ref>
{{cite journal
 |last1=Surko |first1=C. M.
 |last2=Greaves |first2=R. G.
 |date=2004
 |title=Emerging science and technology of antimatter plasmas and trap-based beams
 |journal=[[Physics of Plasmas]]
 |volume=11 |issue=5 |page=2333
 |bibcode=2004PhPl...11.2333S
 |doi=10.1063/1.1651487
}}</ref> This cloud is then recaptured in a second trap near the antiprotons. Manipulations of the trap electrodes then tip the antiprotons into the positron plasma, where some combine with antiprotons to form antihydrogen. This neutral antihydrogen is unaffected by the electric and magnetic fields used to trap the charged positrons and antiprotons, and within a few microseconds the antihydrogen hits the trap walls, where it annihilates. Some hundreds of millions of antihydrogen atoms have been made in this fashion.

In 2005, ATHENA disbanded and some of the former members (along with others) formed the [[ALPHA Collaboration]], which is also based at CERN. The ultimate goal of this endeavour is to test [[CPT symmetry]] through comparison of the [[atomic spectra]] of [[hydrogen]] and antihydrogen (see [[hydrogen spectral series]]).<ref>
{{cite journal
 |last=Madsen |first=N.
 |date=2010
 |title=Cold antihydrogen: a new frontier in fundamental physics
 |journal=[[Philosophical Transactions of the Royal Society A]]
 |volume=368 |issue=1924 |pages=3671–82
 |bibcode=2010RSPTA.368.3671M
 |doi=10.1098/rsta.2010.0026
 |pmid=20603376
|doi-access=free
 }}</ref>

Most of the sought-after high-precision tests of the properties of antihydrogen could only be performed if the antihydrogen were trapped, that is, held in place for a relatively long time. While antihydrogen atoms are electrically neutral, the [[Spin (physics)|spins]] of their component particles produce a [[magnetic moment]]. These magnetic moments can interact with an inhomogeneous magnetic field; some of the antihydrogen atoms can be attracted to a magnetic minimum. Such a minimum can be created by a combination of mirror and multipole fields.<ref>
{{cite journal
 |last1=Pritchard |first1=D. E.
 |last2=Heinz |first2=T.
 |last3=Shen |first3=Y.
 |date=1983
 |title=Cooling neutral atoms in a magnetic trap for precision spectroscopy
 |journal=[[Physical Review Letters]]
 |volume=51 |issue=21 |pages=1983–1986
 |bibcode=1983PhRvL..51.1983T
 |doi=10.1103/PhysRevLett.51.1983
}}</ref> Antihydrogen can be trapped in such a magnetic minimum (minimum-B) trap; in November 2010, the ALPHA collaboration announced that they had so trapped 38 antihydrogen atoms for about a sixth of a second.<ref>
{{cite journal
 |last=Andresen |display-authors=etal
 |date=2010
 |title=Trapped antihydrogen
 |journal=[[Nature (journal)|Nature]]
 |volume=468 |issue=7324 |pages=673–676
 |bibcode=2010Natur.468..673A
 |doi=10.1038/nature09610
 |pmid=21085118
|s2cid=2209534
 }}</ref><ref>
{{cite web
 |title=Antimatter atoms produced and trapped at CERN
 |url=http://public.web.cern.ch/press/pressreleases/Releases2010/PR22.10E.html
 |publisher=[[CERN]]
 |access-date=20 January 2011
 |date=17 November 2010
 |archive-url=https://web.archive.org/web/20110123232026/http://public.web.cern.ch/press/pressreleases/Releases2010/PR22.10E.html
 |archive-date=23 January 2011
 |url-status=dead
 }}</ref> This was the first time that neutral antimatter had been trapped.

On 26 April 2011, ALPHA announced that they had trapped 309 antihydrogen atoms, some for as long as 1,000 seconds (about 17 minutes). This was longer than neutral antimatter had ever been trapped before.<ref>{{cite journal
 |author=ALPHA Collaboration
 |date=2011
 |title=Confinement of antihydrogen for 1,000 seconds
 |url=https://cds.cern.ch/record/1347171
 |journal=[[Nature Physics]]
 |volume=7
 |issue=7
 |pages=558–564
 |arxiv=1104.4982
 |bibcode=2011NatPh...7..558A
 |doi=10.1038/nphys2025
 |s2cid=17151882
 |access-date=22 August 2018
 |archive-date=23 March 2020
 |archive-url=https://web.archive.org/web/20200323082111/https://cds.cern.ch/record/1347171
 |url-status=live
 }}</ref> ALPHA has used these trapped atoms to initiate research into the spectral properties of antihydrogen.<ref>{{Cite journal
 |last1=Amole
 |first1=C.
 |display-authors=etal
 |date=2012
 |title=Resonant quantum transitions in trapped antihydrogen atoms
 |url=https://cds.cern.ch/record/1430040/files/Nature_pre.pdf
 |journal=Nature
 |volume=483
 |issue=7390
 |pages=439–443
 |pmid=22398451
 |bibcode=2012Natur.483..439A
 |hdl=11568/757495
 |doi=10.1038/nature10942
 |s2cid=2321196
 |access-date=25 October 2017
 |archive-date=23 March 2020
 |archive-url=https://web.archive.org/web/20200323082130/https://cds.cern.ch/record/1430040/files/Nature_pre.pdf
 |url-status=live
 }}</ref>

In 2016, a new antiproton decelerator and cooler called ELENA (extra low energy antiproton decelerator) was built. It takes the antiprotons from the antiproton decelerator and cools them to 90&nbsp;keV, which is "cold" enough to study. This machine works by using high energy and accelerating the particles within the chamber. More than one hundred antiprotons can be captured per second, a huge improvement, but it would still take several thousand years to make a [[nanogram]] of antimatter.

The biggest limiting factor in the large-scale production of antimatter is the availability of antiprotons. Recent data released by CERN states that, when fully operational, their facilities are capable of producing ten million antiprotons per minute.<ref>{{cite journal
 |last=Madsen
 |first=N.
 |date=2010
 |title=Cold antihydrogen: a new frontier in fundamental physics
 |journal=[[Philosophical Transactions of the Royal Society A]]
 |volume=368
 |issue=1924
 |pages=3671–82
 |bibcode=2010RSPTA.368.3671M
 |doi=10.1098/rsta.2010.0026
 |pmid=20603376
 |url=https://zenodo.org/record/889475
 |doi-access=free
 |access-date=9 September 2019
 |archive-date=29 March 2020
 |archive-url=https://web.archive.org/web/20200329132655/https://zenodo.org/record/889475
 |url-status=live
 }}</ref> Assuming a 100% conversion of antiprotons to antihydrogen, it would take 100&nbsp;billion years to produce 1&nbsp;gram or 1 [[Mole (unit)|mole]] of antihydrogen (approximately {{val|6.02|e=23}} atoms of anti-hydrogen). However, CERN only produces 1% of the anti-matter Fermilab does, and neither are designed to produce anti-matter. According to Gerald Jackson, using technology already in use today we are capable of producing and capturing 20 grams of anti-matter particles per year at a yearly cost of 670 million dollars per facility.<ref>{{cite journal |last1=Jackson |first1=Gerald |date=December 2022 |title=Antimatter-Based Propulsion for Exoplanet Exploration |url=https://www.ans.org/pubs/journals/nt/article-52262/ |journal=Nuclear Technology |volume=208 |issue=1 |pages=S107–S112|doi=10.1080/00295450.2021.1997057 |bibcode=2022NucTe.208S.107J |doi-access=free }}</ref>

===Antihelium===
Antihelium-3 nuclei ({{SimpleNuclide|anti=yes|helium|3}}) were first observed in the 1970s in proton–nucleus collision experiments at the Institute for High Energy Physics by Y. Prockoshkin's group (Protvino near Moscow, USSR)<ref>
{{cite journal
 |last=Antipov |first=Y. M.
 |display-authors=etal
 |date=1974
 |title=Observation of antihelium3 (in Russian)
 |journal=[[Yadernaya Fizika]]
 |volume=12 |page=311
}}</ref> and later created in nucleus–nucleus collision experiments.<ref>
{{cite journal
 |last=Arsenescu |first=R.
 |display-authors=etal
 |date=2003
 |title=Antihelium-3 production in lead–lead collisions at 158&nbsp;''A''&nbsp;GeV/''c''
 |journal=[[New Journal of Physics]]
 |volume=5 |issue=1 |page=1
 |bibcode=2003NJPh....5....1A
 |doi=10.1088/1367-2630/5/1/301
|doi-access=free
 }}</ref> Nucleus–nucleus collisions produce antinuclei through the coalescence of antiprotons and antineutrons created in these reactions. In 2011, the [[STAR detector]] reported the observation of artificially created antihelium-4 nuclei (anti-alpha particles) ({{SimpleNuclide|anti=yes|helium|4}}) from such collisions.<ref>
{{cite journal
 |last=Agakishiev |first=H.
 |display-authors=etal
 |date=2011
 |title=Observation of the antimatter helium-4 nucleus
 |journal=Nature
 |volume=473 |issue=7347 |pages=353–356
 |arxiv=1103.3312
 |doi=10.1038/nature10079
 |bibcode=2011Natur.473..353S
 |pmid=21516103
|s2cid=118484566
 }}</ref>

The [[Alpha Magnetic Spectrometer]] on the [[International Space Station]] has, as of 2021, recorded eight events that seem to indicate the detection of antihelium-3.<ref>{{cite journal |last1=Leah Crane |title=Antimatter stars may lurk in the solar system's neighbourhood |journal=New Scientist |date=May 1, 2021 |url=https://www.newscientist.com/article/2275563-antimatter-stars-may-lurk-in-the-solar-systems-neighbourhood/ |access-date=1 May 2021 |archive-date=1 May 2021 |archive-url=https://web.archive.org/web/20210501150008/https://www.newscientist.com/article/2275563-antimatter-stars-may-lurk-in-the-solar-systems-neighbourhood/ |url-status=live }}</ref><ref>{{cite journal |last1=Joshua Sokol |title=Giant space magnet may have trapped antihelium, raising idea of lingering pools of antimatter in the cosmos |journal=Science |date=Apr 19, 2017 |doi=10.1126/science.aal1067 |url=https://www.science.org/content/article/giant-space-magnet-may-have-trapped-antihelium-raising-idea-lingering-pools-antimatter |access-date=1 May 2021 |archive-date=1 May 2021 |archive-url=https://web.archive.org/web/20210501145420/https://www.sciencemag.org/news/2017/04/giant-space-magnet-may-have-trapped-antihelium-raising-idea-lingering-pools-antimatter |url-status=live }}</ref>

===Preservation===
<!--===Antimatter trap===!-->

Antimatter cannot be stored in a container made of ordinary matter because antimatter reacts with any matter it touches, annihilating itself and an equal amount of the container. Antimatter in the form of [[charged particle]]s can be contained by a combination of [[electric field|electric]] and [[magnetic field|magnetic]] fields, in a device called a [[Penning trap]]. This device cannot, however, contain antimatter that consists of uncharged particles, for which [[atomic trap]]s are used. In particular, such a trap may use the [[dipole]] moment ([[Electric dipole moment|electric]] or [[Magnetic moment|magnetic]]) of the trapped particles. At high [[vacuum]], the matter or antimatter particles can be trapped and cooled with slightly off-resonant laser radiation using a [[magneto-optical trap]] or [[Magnetic trap (atoms)|magnetic trap]]. Small particles can also be suspended with [[optical tweezers]], using a highly focused laser beam.<ref>
{{cite journal
 |last1=Blaum |first1=K.
 |last2=Raizen |first2=M. G.
 |last3=Quint |first3=W.
 |year=2014
 |title=An experimental test of the weak equivalence principle for antihydrogen at the future FLAIR facility
 |journal=[[International Journal of Modern Physics: Conference Series]]
 |volume=30 |pages=1460264
 |bibcode=2014IJMPS..3060264B
 |doi=10.1142/S2010194514602646
 |hdl=11858/00-001M-0000-001A-152D-1
|hdl-access=free
 }}</ref>

In 2011, [[CERN]] scientists were able to preserve antihydrogen for approximately 17 minutes.<ref>{{cite news|date=9 June 2011|title=Antimatter of Fact|url=http://www.economist.com/node/18802932|newspaper=The Economist|archive-url=https://web.archive.org/web/20140217051839/http://www.economist.com/node/18802932|archive-date=17 February 2014}}</ref> The record for storing antiparticles is currently held by the TRAP experiment at CERN: antiprotons were kept in a Penning trap for 405 days.<ref>{{Cite journal|title=Improved limit on the directly measured antiproton lifetime|journal=New Journal of Physics|year=2017|doi=10.1088/1367-2630/aa7e73|last1=Sellner|first1=S.|last2=Besirli|first2=M.|last3=Bohman|first3=M.|last4=Borchert|first4=M. J.|last5=Harrington|first5=J.|last6=Higuchi|first6=T.|last7=Mooser|first7=A.|last8=Nagahama|first8=H.|last9=Schneider|first9=G.|last10=Smorra|first10=C.|last11=Tanaka|first11=T.|last12=Blaum|first12=K.|last13=Matsuda|first13=Y.|last14=Ospelkaus|first14=C.|last15=Quint|first15=W.|last16=Walz|first16=J.|last17=Yamazaki|first17=Y.|last18=Ulmer|first18=S.|volume=19|issue=8|page=083023|bibcode=2017NJPh...19h3023S|doi-access=free}}</ref> A proposal was made in 2018 to develop containment technology advanced enough to contain a billion anti-protons in a portable device to be driven to another lab for further experimentation.<ref>
{{cite journal|last1=Gibney |first1=E.|year=2018|title=Physicists plan antimatter's first outing – in a van|journal=[[Nature (journal)|Nature]]|volume=554 |issue=7693 |pages=412–413|bibcode=2018Natur.554..412G|doi=10.1038/d41586-018-02221-9|pmid=29469122|s2cid=4448531|doi-access=free}}</ref>

===Cost===
Scientists claim that antimatter is the costliest material to make.<ref name="NASA1999"/> In 2006, Gerald Smith estimated $250&nbsp;million could produce 10 milligrams of positrons<ref>
{{cite web
 |last=Steigerwald |first=B.
 |date=14 March 2006
 |title=New and Improved Antimatter Spaceship for Mars Missions
 |url=http://www.nasa.gov/exploration/home/antimatter_spaceship.html
 |publisher=[[NASA]]
 |quote="A rough estimate to produce the 10 milligrams of positrons needed for a human Mars mission is about 250 million dollars using technology that is currently under development," said Smith.
 |access-date=11 June 2010
 |archive-url=https://web.archive.org/web/20110806181954/http://www.nasa.gov/exploration/home/antimatter_spaceship.html
 |archive-date=6 August 2011
 |url-status=live
}}</ref> (equivalent to $25&nbsp;billion per gram); in 1999, NASA gave a figure of $62.5&nbsp;trillion per gram of antihydrogen.<ref name="NASA1999">
{{cite web
 |date=12 April 1999
 |title=Reaching for the stars: Scientists examine using antimatter and fusion to propel future spacecraft
 |url=https://science.nasa.gov/science-news/science-at-nasa/1999/prop12apr99_1
 |publisher=[[NASA]]
 |quote=Antimatter is the most expensive substance on Earth
 |access-date=11 June 2010
 |archive-url=https://web.archive.org/web/20100612110153/http://science.nasa.gov/science-news/science-at-nasa/1999/prop12apr99_1/
 |archive-date=12 June 2010
 |url-status=live
}}</ref> This is because production is difficult (only very few antiprotons are produced in reactions in particle accelerators) and because there is higher demand for other uses of [[particle accelerator]]s. According to CERN, it has cost a few hundred million [[Swiss franc]]s to produce about 1&nbsp;billionth of a gram (the amount used so far for particle/antiparticle collisions).<ref>
{{cite web
 |date=2001
 |title=Antimatter Questions & Answers
 |url=http://livefromcern.web.cern.ch/livefromcern/antimatter/FAQ1.html
 |archive-url=https://archive.today/20080421220420/http://livefromcern.web.cern.ch/livefromcern/antimatter/FAQ1.html
 |archive-date=2008-04-21
 |publisher=[[CERN]]
 |access-date=24 May 2008
 |url-status=dead
}}</ref> In comparison, to produce the first atomic weapon, the cost of the [[Manhattan Project]] was estimated at $23&nbsp;billion with inflation during 2007.<ref>
{{cite web
 |title=Manhattan Project: CTBTO Preparatory Commission
 |url=http://www.ctbto.org/nuclear-testing/history-of-nuclear-testing/manhattan-project/
 |archive-url=https://web.archive.org/web/20141222033224/http://www.ctbto.org/nuclear-testing/history-of-nuclear-testing/manhattan-project/
 |archive-date=22 December 2014
 |url-status=live
}}</ref>

Several studies funded by [[NASA Innovative Advanced Concepts]] are exploring whether it might be possible to use magnetic scoops to collect the antimatter that occurs naturally in the [[Van Allen radiation belt|Van Allen belt]] of the Earth, and ultimately the belts of gas giants like [[Jupiter]], ideally at a lower cost per gram.<ref>
{{cite web
 |last=Bickford |first=J.
 |title=Extraction of Antiparticles Concentrated in Planetary Magnetic Fields
 |url=https://www.centauri-dreams.org/wp-content/Bickford_Phase_II.pdf
 |publisher=[[NASA]] and Draper Laboratory
 | date= Aug 2007
|archive-url=https://web.archive.org/web/20080723210113/http://www.niac.usra.edu/files/studies/abstracts/1071Bickford.pdf
 |archive-date=23 July 2008
 |url-status=live
 }}</ref>