Twin Quasar

The Twin Quasar Q0957+561
Observation data (Epoch J2000)
Constellation	Ursa Major
Right ascension	10h 01m 20.99s
Declination	+55° 53′ 56.5″
Redshift	1.413
Distance	7,800,000,000 ly (2,400,000,000 pc)
Type	Rad
Apparent dimensions (V)	0.42´× 0.22´
Apparent magnitude (V)	16.7
Other designations
Double Quasar, QSO 0957+561, 8C 0958+561, PGC 2518326
See also: Quasar, List of quasars

The Twin Quasar (Double Quasar) or Old Faithful is also known as Q0957+561, or QSO 0957+561. It was the first identified gravitationally lensed object.

Quasar

Q0957+561 A (QSO 0957+561 A) and Q-0957+561 B (QSO 0957+561 B) is a double-imaged quasar, meaning that an intervening mass concentration between Earth and the quasar bends light so that two images of the quasar appear in the sky. This is known as gravitational lensing, and is a consequence of Einsteinian warped space-time. The quasar lies at redshift z = 1.41(8.7 billion ly), while the lensing galaxy lies at redshift z = 0.355 (3.7 billion ly). The lensing galaxy lies almost in line with the B image, lying 1" off. The quasar lies 10" north of NGC 3079, in the constellation Ursa Major.

The Twin Quasar's two images are separated by 6". Both images have an apparent magnitude of 17, with the A component having 16.7 and the B component having 16.5 . There is a 417 ± 3 day time lag between the two images.

Lens

The lensing galaxy, YGKOW G1 (sometimes called G1 or Q0957+561 G1), is a giant elliptical (type cD) lying within a cluster of galaxies that also contribute to the lensing. A microlensing event in 1996 observed by R. E. Schild in the A lobe has led to a controversial, and unconfirmable theory that there is a planet approximately three Earth masses in size in the lensing galaxy. The speculation cannot be confirmed because the chance alignment that led to its discovery will never happen again. If it could be confirmed, however, it would make it the most distant known planet.

Magnetospheric Eternally Collapsing Objects (MECO) In Radio Loud and Radio Quiet Quasars

R. E. Schild, D. Leiter, and S. Robertson have announced findings which suggest that the object at the heart of the radio loud quasar Q0957+561 is not a supermassive black hole, as is currently believed to be the case for all quasars. Schild and his team at the Harvard-Smithsonian Center for Astrophysics found that the jets originated 8000 AU from the poles of the centre, in a region 1000AU across. In addition they found that the accretion disc in this quasar appeared to be truncated at 2000AU from the centre, and the inner edge surrounding the apparently empty inner region of the disc contained a very thin annular region that was found to be intensely radiating. There also appeared to be a broad conic wind outflow from the accretion disc which created a luminous Broad Line Emission Region Elvis structure (cf. Martin Elvis). On the basis of these observations they came to the conclusion that "This quasar appears to be dynamically dominated by an intrinsic magnetic field which is internally anchored to its central, rotating supermassive compact object".

In "radio loud" quasars, which make up about 10% of the total quasar populations, some of that gas is forcefully ejected outward in two opposing jets at nearly the speed of light. On the other hand the remaining 90% of the quasars do not exhibit any jet structure and for that reason are "radio quiet". In order to better understand the difference between the two types of quasars, theorists struggle to understand the physics of the accretion disk and jets, while observers struggle to peer into the quasar's heart. However the manner in which the "central engine" is able to turn on radio emitting jet structures in radio loud quasars, while also being able to turn off the radio emitting jet structure in radio quiet quasars, is difficult problem for both theorists and observers because the central regions of quasars are so compact and the quasars so far away from Earth.

Using newly developed optical telescope techniques involving gravitational micro-lensing and reverberation analysis, Rudy Schild and his colleagues have also studied the internal structure of the radio quiet quasar Q2237 (known as the Einstein Cross), as well as the radio loud quasar Q0957 (known as the Twin) both of which are located more than 9 billion light-years from Earth. These two quasars, which are in distinctly different spectral states, have been observed to have central compact objects containing masses on the order of 3-4 billion Suns. For this reason most astrophysicists would consider the central objects in these two quasars to be "black holes," but Schild, Leiter, and Robertson's research has suggested otherwise. "We don't call the central objects in these quasars black holes because our observations indicate that these two quasars have central compact objects which contain internally anchored magnetic fields that are able to penetrate through the surface of their collapsed central objects and interact with the quasars accretion disk and its environment," they commented.

The researchers chose Q0957 and Q2237 because of their association with natural cosmic lenses. The gravity of nearby galaxies bends space, forming multiple images of the distant quasars and magnifying their light. Stars and planets within nearby galaxies can also affect the quasars light, causing small fluctuations in brightness (in a process called "micro-lensing") when they drift into the line of sight between Earth and the quasars.

Using this micro-lensing-reverberation technique on the radio loud quasar Q0957 Schild monitored the quasar's brightness for a period of 20 years, and led an international consortium of observers operating 14 telescopes to keep the object under steady around-the-clock watch at critical times. "With micro-lensing, we were able to discern more detail about the so-called 'black hole' in this quasar which is two- thirds of the way to the edge of the visible universe than we can from the black hole at the center of the Milky Way," said Schild. Through careful analysis, the team teased out details about the inner structure of this quasar For example, their calculations pinpointed the location where the jets form. "How when and where do these jets form? Even after 60 years of radio observations, we had no answer. Now the evidence is in, and we know," said Schild.

Schild, Leiter, and Robertson found that the jets in the radio loud quasar Q0957 appear to emerge from two regions 1,000 astronomical units in size (about 25 times larger than the Pluto-Sun distance) located 8,000 astronomical units directly above the poles of the central compact object. (An astronomical unit is defined as the average distance from the Earth to the Sun, or 93 million miles). However, that location would be expected only if the jets were powered by reconnecting magnetic field lines that were anchored to the rotating super massive compact object within the quasar. By interacting with a surrounding accretion disk, such spinning magnetic field lines spool up, winding tighter and tighter until they explosively unite, reconnect and break, releasing huge amounts of energy that power the jets. "This quasar appears to be dynamically dominated by an intrinsic magnetic field which is internally anchored to its central, rotating super massive compact object," they stated.

Since standard black hole models were found to be unable to explain the observed internal structure seen in the quasar Q0957, Schild and his colleagues, Darryl Leiter (Marwood Astrophysics Research Center and currenty a visitor at the National Radio Astronomy Observatory in Charlottesville Virginia) and Stanley Robertson (Southwestern Oklahoma State University), were led to propose a revolutionary new general relativistic theory for the quasar Q0957 in which the structure of the dominant magnetic field is intrinsic to the quasar's central, super massive compact object, rather than only being part of the accretion disk as thought by most researchers. "Our finding challenges the accepted view of black holes," said Leiter. "We've even proposed a new name for them Magnetospheric Eternally Collapsing Objects, or MECO," a magnetic generalization of the name coined in 1998 by Indian astrophysicist Abhas Mitra. This research suggests that, in addition to its mass and spin, the central compact object in Q0957 may have physical properties more like a highly red shifted, spinning magnetic dipole than like a black hole. According to this theory, a MECO does not have an event horizon, so any matter that is able to get by the magnetic propeller is gradually slowed down and stopped at the MECO's highly red shifted surface, with just a weak signal connecting the radiation from that matter to a distant observer. For this reason this signal has not been detected from Q0957 since it is very hard to observe.

On the basis of these observations and analysis Schild, Leiter, and Robertson were led to the conclusion that a simple and unified answer to the long-standing question: "Why are some quasars radio loud?" emerges naturally if the central objects of quasars are MECO, with radio-loud and radio-quiet states similar to the case of galactic black hole candidates.

MECO and the Strong Principle of Equivalence

In general relativity, preservation of the strong principle of equivalence (SPOE) requires that special relativity must hold locally for all time-like observers in all of spacetime. The existence of MECO is implied by the idea that Nature requires that the SPOE must be dynamically preserved everywhere in spacetime for the timelike world lines of massive particles or fluids under the influence of both gravitational and non-gravitational forces. Preservation of the SPOE requires that the frame of reference of the co-moving observer in the massive collapsing fluid must always be connected to the frame of reference of a stationary observer by special relativistic transformations with a physical 3-speed that is less than the speed of light (Schild, R., Leiter, D., & Robertson, S. 2006, AJ, 132, 420 -(SLR06).

Since the left-hand side of the Einstein equation cannot by itself dynamically enforce the preservation of the SPOE, it follows that for collapsing objects there must exist SPOE-preserving non-gravitational processes in nature which must always be included in the energy–momentum tensor on the right-hand side of the Einstein equation. It was in this manner that the general relativistic MECO solutions to the Einstein-Maxwell equations were discovered, as was shown in the papers (Robertson, S., & Leiter, D. (2002), ApJ, 565, 447; Robertson, S., & Leiter, D. (2003) ApJ, 596, L203; Robertson, S., & Leiter, D. (2004), MNRAS, 350, 1391; and developed in more detail in Appendices 1–10 of Schild et al. (2005),(Schild, R., Leiter, D., & Robertson, S. (2005), arXiv astro-ph/0505518. There it was shown that for a collapsing body, the structure and radiation transfer properties of the energy–momentum tensor on the right-hand side of the Einstein field equations, could describe a collapsing radiating object which contained equipartition magnetic fields that generated a highly red-shifted Eddington limited secular collapse process. This collapse process was shown to preserve the SPOE by dynamically preventing trapped surfaces, that lead to event horizons, from forming. In Appendices 1–10 of Schild et al. (2005) it was shown that, by using the Einstein–Maxwell equations and quantum electrodynamics in the context of general relativistic plasma astrophysics, it was possible to virtually stop and maintain a slow (many Hubble times!), steady collapse of a compact physical plasma object outside of its Schwarzschild radius. The non-gravitational force was Compton photon pressure generated by synchrotron radiation from an intrinsic equipartition magnetic dipole field contained within the compact object. The rate of collapse is controlled by radiation at the local Eddington limit, but from a highly red shifted surface with an extremely small photon escape cone. In Appendix 9 and 10 of Schild et al. (2005) it was shown that the equatorial poloidal magnetic field, associated with a locally Eddington limited secular rate of collapse of the exterior surface, was strong enough to spontaneously create bound electron-positron pairs in the surface plasma of the MECO which contribute to the general relativistic surface drift currents, within the pair dominated plasma at the MECO surface. These electron-positron drift currents on the MECO surface generate the magnetic fields which create the MECO’s distantly observed intrinsic magnetic moment. Within the context of the MECO’s Eddington limited secular balance, the action of this QED pair production process was shown to be sufficient to stabilize the collapse rate of the MECO surface. For the collapsing, radiating pair dominated plasma associated with the MECO, the corresponding exterior solution to the Einstein equation is described by the time dependent Vaidya metric, where no coordinate transformation between MECO Vaidya metric and the black hole Kerr–Schild metric exists.

Since the highly red shifted Eddington limited MECO Vaidya metric solutions preserve the SPOE they do not have event horizons and the MECO exhibit distantly observed slowly rotating intrinsic magnetic dipole moments which can interact with their surrounding accretion disk environments. In this way the super massive MECO existing in the center of quasar Q0957 revealed itself by generating unique observable magnetic effects on the accretion disk environment (i.e. the Schild-Vakulik Structure discussed in (SLR06)) which observationally distinguished it from that of a central Black Hole.

This research was published in the March 2008 issue of Astronomical Journal, 135, 947 (2008). Also see the related publication Astronomical Journal, 132, 420,(2006) and http://arxiv.org/abs/astro-ph/0505518

.

See also

• Extrasolar planet
• Hypothetical planet
• R. E. Schild
• Darryl Leiter
• Stanley Robertson
• Magnetospheric eternally collapsing object, MECO
• Multiple images (gravitational lensing)
• Einstein Cross

External links

• Q0957+561: Die historisch erste Linse mit Quasar - The University of Cologne.
• Q0957+561 - CCD Image Based on 45-min total exposure - March/2007.
• Research Sheds New Light On Quasars - SpaceDaily July 26, 2006.
• Mysterious quasar casts doubt on black holes - New Scientist, July 27, 2006.

References

• Observations Supporting the Existence of an Intrinsic Magnetic Moment Inside the Central Compact Object Within the Quasar Q0957+561 Rudolph E. Schild, Darryl J. Leiter, Stanley L. Robertson (arXiv) Wed, 25 May 2005 17:37:09 GMT
• Simbad
• http://www.exoplaneten.de/Q0957+561/english.html