Editing Magnetar (section)

=== Magnetic field ===
Magnetars are characterized by their extremely powerful magnetic fields of ~10<sup>9</sup> to 10<sup>11</sup> [[Tesla (unit)|T]].<ref name="mcgill"/> These magnetic fields are a hundred million times stronger than any man-made magnet,<ref>{{cite web |url=http://www.fzd.de/db/Cms?pNid=1482 |title=HLD user program, at Dresden High Magnetic Field Laboratory |access-date = 2009-02-04}}</ref> and about a trillion times more powerful than the [[Earth's magnetic field|field surrounding Earth]].<ref>{{cite news |url=https://skyandtelescope.org/astronomy-news/the-brightest-blast |title=The Brightest Blast |first=Robert |last=Naeye |date=February 18, 2005 |work=[[Sky & Telescope]] |access-date=10 November 2020}}</ref> Earth has a [[geomagnetic]] field of 30–60 microteslas, and a [[neodymium magnet|neodymium-based, rare-earth magnet]] has a field of about 1.25 tesla, with a magnetic energy density of 4.0 × 10<sup>5</sup> J/m<sup>3</sup>. A magnetar's 10<sup>10</sup> tesla field, by contrast, has an energy density of {{val|4.0|e=25|u=J/m3}}, with an [[Mass–energy equivalence#Massless particles|''E''/''c''<sup>2</sup>]] mass density more than 10,000 times that of [[lead]]. The magnetic field of a magnetar would be lethal even at a distance of 1,000&nbsp;km due to the strong magnetic field distorting the electron clouds of the subject's constituent atoms, rendering the chemistry of sustaining life impossible.<ref>{{cite web |last=Duncan |first=Robert |title='MAGNETARS', SOFT GAMMA REPEATERS & VERY STRONG MAGNETIC FIELDS |url=http://solomon.as.utexas.edu/magnetar.html |archive-url= |archive-date= |access-date= |publisher=University of Texas}}</ref> At a distance of halfway from Earth to the Moon, an average distance between the Earth and the Moon being {{Convert|384400|km|abbr=in}}, a magnetar could wipe information from the magnetic stripes of all [[credit card]]s on Earth.<ref>{{cite web |url=http://www.nasa.gov/vision/universe/watchtheskies/swift_nsu_0205.html |title=Cosmic Explosion Among the Brightest in Recorded History |date=February 18, 2005 |first=Christopher |last=Wanjek |publisher=[[NASA]] |access-date=17 December 2007}}</ref> {{as of|2020}}, they are the most powerful magnetic objects detected throughout the universe.<ref name="journal2">Kouveliotou, C.; Duncan, R. C.; Thompson, C. (February 2003). "[http://solomon.as.utexas.edu/~duncan/sciam.pdf Magnetars] {{webarchive |url=https://web.archive.org/web/20070611144829/http://solomon.as.utexas.edu/~duncan/sciam.pdf |date=2007-06-11 }}". ''[[Scientific American]]''; Page 36.</ref><ref>{{cite web |url=https://science.nasa.gov/newhome/headlines/ast20may98_1.htm |title="Magnetar" discovery solves 19-year-old mystery |date=May 20, 1998 |first=Dave |last=Dooling |work=Science@NASA Headline News |access-date=17 December 2007 |archive-url=https://web.archive.org/web/20071214033454/http://science.nasa.gov/newhome/headlines/ast20may98_1.htm |archive-date=14 December 2007 |url-status=dead }}</ref>

As described in the February 2003 ''[[Scientific American]]'' cover story, remarkable things happen within a magnetic field of magnetar strength. "[[X-ray]] [[photon]]s readily split in two or merge. The vacuum itself is [[Vacuum_polarization|polarized]], becoming strongly [[birefringent]], like a [[calcite]] crystal. [[Atom]]s are deformed into long cylinders thinner than the quantum-relativistic [[de Broglie wavelength]] of an electron."<ref name="journal"/> In a field of about 10<sup>5</sup> teslas [[atomic orbital]]s deform into rod shapes. At 10<sup>10</sup> teslas, a [[hydrogen atom]] becomes 200 times as narrow as its normal diameter.<ref name="journal">Kouveliotou, C.; Duncan, R. C.; Thompson, C. (February 2003). "[http://solomon.as.utexas.edu/magnetar.html#SciAm Magnetars]". ''[https://solomon.as.utexas.edu/sciam.pdf Scientific American]''; Page 41.</ref>

====Origins of magnetic fields====
The dominant model of the strong fields of magnetars is that it results from a [[magnetohydrodynamic dynamo]] process in the turbulent, extremely dense conducting fluid that exists before the neutron star settles into its equilibrium configuration.<ref>{{Cite journal |last1=Thompson |first1=Christopher |last2=Duncan |first2=Robert C. |date=1993 |title=Neutron Star Dynamos and the Origins of Pulsar Magnetism |url=https://articles.adsabs.harvard.edu/pdf/1993ApJ...408..194T |journal=Astrophysical Journal |volume=408 |pages=194–217 |doi=10.1086/172580 |bibcode=1993ApJ...408..194T |via=NASA Astrophysics Data System |doi-access= }}</ref> These fields then persist due to persistent currents in a proton-superconductor phase of matter that exists at an intermediate depth within the neutron star (where neutrons predominate by mass). A similar magnetohydrodynamic dynamo process produces even more intense transient fields during [[Neutron star merger|coalescence of a pair of neutron stars]].<ref>{{Cite journal
|last1        = Price
|first1       = Daniel J.
|last2        = Rosswog
|first2       = Stephan
|title        = Producing Ultrastrong Magnetic Fields in Neutron Star Mergers
|doi          = 10.1126/science.1125201
|journal      = Science
|volume       = 312
|issue        = 5774
|pages        = 719–722
|date         = May 2006
|pmid         = 16574823
|arxiv        = astro-ph/0603845
|url          = http://users.monash.edu.au/~dprice/research/nsmag/
|bibcode      = 2006Sci...312..719P
|s2cid        = 30023248
|access-date  = 2012-07-13
|archive-date = 2018-07-17
|archive-url  = https://web.archive.org/web/20180717141702/http://users.monash.edu.au/~dprice/research/nsmag/
|url-status   = dead
}} {{open access}}</ref> An alternative model is that they simply result from the collapse of stars with unusually strong magnetic fields.<ref>{{Cite journal
| last1 = Zhou | first1 = Ping
| last2 = Vink | first2 = Jacco
| last3 = Safi-Harb | first3 = Samar
| last4 = Miceli | first4 = Marco
| title = Spatially resolved X-ray study of supernova remnants that host magnetars: Implication of their fossil field origin
| doi = 10.1051/0004-6361/201936002
| journal = Astronomy & Astrophysics
| volume = 629
| issue = A51
| pages = 12
| date = September 2019
| arxiv = 1909.01922
| bibcode = 2019A&A...629A..51Z
| s2cid = 201252025
}} {{open access}}</ref>