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MY'STORY

The MOVE Fire

This is a personal recollection on the Move fire on May 13, 1985 Philadelphia police fired thousands of rounds at the MOVE house, city officials approved dropping an explosive device on the roof, the resulting fire was allowed to burn, 11 people—including five children—died, and 61 homes were destroyed. Philadelphia City Council later called it a “brutal attack carried out by the City of Philadelphia on its own citizens” and acknowledged that no individual faced criminal consequences for the bombing. One timeline correction worth preserving for the BHP record: the major previous MOVE-police confrontation was August 8, 1978, about seven years before the bombing, not a year or two earlier. Officer James Ramp was killed, other police and firefighters were wounded, nine MOVE members were later convicted, and television cameras recorded police beating Delbert Africa during his arrest. The 1985 MOVE Commission later specifically criticized city planners for failing to adequately use lessons from that 1978 confrontation. And that actually strengthens the point you’re making: 1985 did not happen without precedent or institutional memory. There had already been a deadly confrontation with MOVE, years of conflict, negotiations and police involvement before Osage Avenue.

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BLACK FACTS
The Truths They Never Taught You...

The Violence That Helped Spark the NAACP

In August 1908, a white mob attacked Springfield, Illinois’s Black community, destroying homes and businesses and lynching two Black men. National outrage over the violence helped spur the movement that created the NAACP the following year.

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Wikipedia

PAMELA detector

For other uses, see PAMELA (disambiguation).

PAMELA
Organization PAMELA group
Mission Type Cosmic Ray
Host Satellite Resurs DK1
Launch 15 June 2006
Launch vehicle Soyuz-FG
Launch site Baikonur Cosmodrome
Mission duration 3 years (planned),
9 years, 7 months and 23 days (achieved)
Mission end 7 February 2016
Mass 470 kg
Max length 1300 mm
Power consumption 335 Watts
Webpage PAMELA homepage
Orbital elements (Resurs DK1)
Inclination 70 degrees
Orbit quasi-polar elliptical
Min altitude 360 km
Max altitude 604 km
Period 94.02 min

PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) was a cosmic ray research module attached to an Earth orbiting satellite. PAMELA was launched on 15 June 2006 and was the first satellite-based experiment dedicated to the detection of cosmic rays, with a particular focus on their antimatter component, in the form of positrons and antiprotons. Other objectives included long-term monitoring of the solar modulation of cosmic rays, measurements of energetic particles from the Sun, high-energy particles in Earth's magnetosphere and Jovian electrons. It was also hoped that it may detect evidence of dark matter annihilation.[1] PAMELA operations were terminated in 2016,[2] as were the operations of the host-satellite Resurs-DK1. The experiment was a recognized CERN experiment (RE2B).[3][4]

Development and launch

[edit]

PAMELA was the largest device up to the time built by the Wizard collaboration, which includes Russia, Italy, Germany and Sweden and has been involved in many satellite and balloon-based cosmic ray experiments such as Fermi-GLAST. The 470 kg, US$32 million (EU€24.8 million, UK£16.8 million) instrument was originally projected to have a three-year mission. However, this durable module remained operational and made significant scientific contributions until 2016.

PAMELA is mounted on the upward-facing side of the Resurs-DK1 Russian satellite.[1] It was launched by a Soyuz rocket from Baikonur Cosmodrome on 15 June 2006. PAMELA has been put in a polar elliptical orbit at an altitude between 350 and 610 km, with an inclination of 70°.

Design

[edit]

The apparatus is 1.3 m high, has a total mass of 470 kg and a power consumption of 335 W. The instrument is built around a permanent magnet spectrometer with a silicon microstrip tracker that provides rigidity and dE/dx information. At its bottom is a silicon-tungsten imaging calorimeter, a neutron detector and a shower tail scintillator to perform lepton/hadron discrimination. A Time of Flight (ToF), made of three layers of plastic scintillators, is used to measure the velocity and charge of the particle. An anticounter system made of scintillators surrounding the apparatus is used to reject false triggers and albedo particles during off-line analysis.[5]

Sensitivity[1]
Particle Energy Range
Antiproton flux 80 MeV – 190 GeV
Positron flux 50 MeV – 270 GeV
Electron flux up to 400 GeV
Proton flux up to 700 GeV
Electron/positron flux up to 2 TeV
Light nuclei (up to Z=6) up to 200 GeV/n
Light isotopes (D, 3He) up to 1 GeV/n
Antinuclei search sensitivity better than 10−7 antiHe/He

Results

[edit]

Preliminary data (released August 2008, ICHEP Philadelphia) indicate an excess of positrons in the range 10–60 GeV. This is thought to be a possible sign of dark matter annihilation:[6][7] hypothetical WIMPs colliding with and annihilating each other to form gamma rays, matter and antimatter particles. Another explanation considered for the indication mentioned above is the production of electron-positron pairs on pulsars with subsequent acceleration in the vicinity of the pulsar.

The first two years of data were released in October 2008 in three publications.[8][9] The positron excess was confirmed and found to persist up to 90 GeV. Surprisingly, no excess of antiprotons was found. This is inconsistent with predictions from most models of dark matter sources, in which the positron and antiproton excesses are correlated.

A paper, published on 15 July 2011, confirmed earlier speculation that the Van Allen belt could confine a significant flux of antiprotons produced by the interaction of the Earth's upper atmosphere with cosmic rays.[10] The energy of the antiprotons has been measured in the range of 60–750 MeV. Cosmic rays collide with atoms in the upper atmosphere creating antineutrons, which in turn decay to produce the antiprotons. They were discovered in a part of the Van Allen belt closest to Earth.[11] When an antiproton interacts with a normal particle, both are annihilated. Data from PAMELA indicated that these annihilation events occurred a thousand times more often than would be expected in the absence of antimatter. The data that contained evidence of antimatter were gathered between July 2006 and December 2008.[12][13]

Boron and carbon flux measurements were published in July 2014,[14] important to explaining trends in cosmic ray positron fraction.[15]

The summary document of the operations of PAMELA was published in 2017.[2]

In 2017, data from the HAWC Collaboration indicated that the increase in flux of positrons from the two nearest pulsars (Geminga and Monogem) is roughly equivalent to the excess originally observed by PAMELA.[16]

Sources of error

[edit]

Between 1 and 100 GeV, PAMELA is exposed to one hundred times as many electrons as antiprotons. At 1 GeV there are one thousand times as many protons as positrons and at 100 GeV ten thousand times as many. Therefore, to correctly determine the antimatter abundances, it is critical that PAMELA is able to reject the matter background. The PAMELA collaboration claimed in "The electron hadron separation performance of the PAMELA electromagnetic calorimeter" that less than one proton in 100,000 is able to pass the calorimeter selection and be misidentified as a positron when the energy is less than 200 GeV.

The ratio of matter to antimatter in cosmic rays of energy less than 10 GeV that reach PAMELA from outside the Solar System depends on solar activity and in particular on the point in the 11 year solar cycle. The PAMELA team has invoked this effect to explain the discrepancy between their low energy results and those obtained by CAPRICE, HEAT and AMS-01, which were collected during that half of the cycle when the solar magnetic field had the opposite polarity.

These results are consistent with the series of positron / electron measurements obtained by AESOP, which has spanned coverage over both polarities. Also the PAMELA experiment has contradicted an earlier claim by the HEAT experiment of anomalous positrons in the 6 GeV to 10 GeV range.

See also

[edit]
  • AMS-02 is a high energy physics experiment mounted to the exterior of the International Space Station featuring advanced particle identification and large acceptance of 0.3m2sr. AMS-02 has been in operation since May 2011. More than 100 billion charged cosmic ray events were recorded by AMS so far.

References

[edit]
  1. ^ a b c Vincenzo Buttaro (ed.). "The Space Mission PAMELA". Retrieved 4 September 2009.
  2. ^ a b Adriani, O; et al. (PAMELA Collaboration) (2018). "Ten Years of PAMELA in Space". Rivista del Nuovo Cimento. 10 (2017): 473–522. arXiv:1801.10310. Bibcode:2018arXiv180110310A. doi:10.1393/ncr/i2017-10140-x. S2CID 119078426.
  3. ^ "Recognized Experiments at CERN". The CERN Scientific Committees. CERN. Archived from the original on 13 June 2019. Retrieved 20 January 2020.
  4. ^ "RE2B/PAMELA: A Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics". CERN. Retrieved 20 January 2020.
  5. ^ Casolino, M; et al. (2008). "Launch of the Space experiment PAMELA". Advances in Space Research. 42 (3): 455–466. arXiv:0708.1808. Bibcode:2008AdSpR..42..455C. doi:10.1016/j.asr.2007.07.023. S2CID 119608020.
  6. ^ Brumfiel, Geoff (14 August 2008). "Physicists await dark-matter confirmation". Nature. 454 (7206): 808–809. doi:10.1038/454808b. PMID 18704050.
  7. ^ Cholis, Ilias; Finkbeiner, Douglas P; Goodenough, Lisa; Weiner, Neal (2009). "The PAMELA Positron Excess from Annihilations into a Light Boson". Journal of Cosmology and Astroparticle Physics. 2009 (12): 007. arXiv:0810.5344. Bibcode:2009JCAP...12..007C. doi:10.1088/1475-7516/2009/12/007. S2CID 73574983.
  8. ^ Casolino, M; et al. (2008). "Two years of flight of the Pamela experiment: Results and perspectives". Journal of the Physical Society of Japan. 78: 35–40. arXiv:0810.4980. Bibcode:2009JPSJ...78S..35C. doi:10.1143/JPSJS.78SA.35. S2CID 119187767.
  9. ^ Adriani, O; et al. (2009). "Observation of an anomalous positron abundance in the cosmic radiation". Nature. 458 (7238): 607–609. arXiv:0810.4995. Bibcode:2009Natur.458..607A. doi:10.1038/nature07942. PMID 19340076. S2CID 11675154.
  10. ^ Adriani, O.; et al. (2011). "The Discovery of Geomagnetically Trapped Cosmic-Ray Antiprotons". The Astrophysical Journal Letters. 737 (2): L29. arXiv:1107.4882. Bibcode:2011ApJ...737L..29A. doi:10.1088/2041-8205/737/2/L29.
  11. ^ Than, Ker (10 August 2011). "Antimatter Found Orbiting Earth—A First". National Geographic Society. Archived from the original on 10 October 2011. Retrieved 12 August 2011.
  12. ^ Cowen, Ron (9 August 2011). "Antimatter Belt Found Circling Earth". Science. Archived from the original on 24 October 2011. Retrieved 12 August 2011.
  13. ^ Chung, Emily (8 August 2011). "Antimatter belt surrounds Earth". CBC News. Retrieved 12 August 2011.
  14. ^ Adriani, O; et al. (31 July 2014). "Measurement of Boron and Carbon Fluxes in Cosmic Rays with the Pamela Experiment". Astrophysical Journal. 791 (2): 93. arXiv:1407.1657. Bibcode:2014ApJ...791...93A. doi:10.1088/0004-637X/791/2/93. S2CID 53002540.
  15. ^ Cholis, Ilias; Hooper, Dan (24 February 2014). "Constraining the origin of the rising cosmic ray positron fraction with the boron-to-carbon ratio". Physical Review D. 89 (4) 043013. arXiv:1312.2952. Bibcode:2014PhRvD..89d3013C. doi:10.1103/PhysRevD.89.043013. S2CID 96470471.
  16. ^ Hooper, Dan (2018). "TASI Lectures on Indirect Searches for Dark Matter". Proceedings of Theoretical Advanced Study Institute Summer School 2018 "Theory in an Era of Data" — PoS(TASI2018). p. 10. arXiv:1812.02029. Bibcode:2018tasi.confE..10H. doi:10.22323/1.333.0010. S2CID 119494364.
[edit]

Source: Wikipedia. Article content is retrieved live through the MediaWiki API.

Wikipedia

PAMELA detector

PAMELA (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) was a cosmic ray research module attached to an Earth orbiting satellite. PAMELA was launched on 15 June 2006 and was the first satellite-based experiment dedicated to the detection of cosmic rays, with a particular focus on their antimatter component, in the form of positrons and antiprotons. Other objectives included long-term monitoring of the solar modulation of cosmic rays, measurements of energetic particles from the Sun, high-energy particles in Earth's magnetosphere and Jovian electrons. It was also hoped that it may detect evidence of dark matter annihilation. PAMELA operations were terminated in 2016, as were the operations of the host-satellite Resurs-DK1. The experiment was a recognized CERN experiment (RE2B).

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Wikipedia

Pamela Woodard

Pamela K. Woodard is an American radiologist specializing in cardiovascular imaging. She is the Elizabeth E. Mallinckrodt Professor of Radiology and the Director the Mallinckrodt Institute of Radiology at Washington University School of Medicine. She also holds appointments as a professor of Internal Medicine, Pediatrics, and Biomedical Engineering at the Washington University in St. Louis. She was elected a Fellow of the American Association for the Advancement of Science in 2022 and a member of the National Academy of Medicine in 2025.

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Wikipedia

Pamela Mosier-Boss

Pamela A. Mosier-Boss is an American analytical chemist who spent her career at the Naval Information Warfare Center Pacific. Her research considered the development of environmental sensors and low-energy nuclear reaction.

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Wikipedia

Polygraph

A polygraph, often incorrectly referred to as a lie detector, is a device that measures and records several clinical biomarkers, such as blood pressure, pulse, respiratory rate, and skin conductivity, and it is used while a person answers a series of questions to purportedly detect lies. Polygraphic assessments rely on the discredited assumption that some physiological mechanisms or functional state, and their variations thereof, could reliably account for psychophysiological phenomena supposedly invoked by (the act of) lying, though polygraphy is considered pseudoscience by the scientific community. The belief underpinning the use of the polygraph is that deceptive answers will produce physiological responses that can be differentiated from those associated with non-deceptive answers; however, there are no specific physiological reactions associated with lying, making it difficult to identify factors that separate those who are lying from those who are telling the truth. In some countries, polygraphs are used as an interrogation tool with criminal suspects or candidates for sensitive public or private sector employment. Some United States law enforcement and federal government agencies, as well as many police departments, use polygraph examinations to interrogate suspects and screen new employees. Within the US federal government, a polygraph examination is also referred to as a "psychophysiological detection of deception examination". Assessments of polygraphy by scientific and government bodies generally suggest that polygraphs are highly inaccurate, may easily be defeated by countermeasures, and are an imperfect or invalid means of assessing truthfulness. A comprehensive 2003 review by the National Academy of Sciences of existing research concluded that there was "little basis for the expectation that a polygraph test could have extremely high accuracy", while the American Psychological Association has stated that "most psychologists agree that there is little evidence that polygraph tests can accurately detect lies." For this reason, the use of polygraphs to detect lies is considered a form of either pseudoscience or junk science.

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TOPIC OF THE DAY

Greenwood / Black Wall Street

Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.

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TRIVIA QUESTION OF THE DAY

Which Black woman became the first elected to the United States Congress?

Shirley Chisholm, elected in 1968.