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Wilhelm Röntgen


Wilhelm Röntgen

From Wikipedia, the free encyclopedia
Wilhelm Röntgen

BornWilhelm Conrad Röntgen
27 March 1845
Lennep, Prussia
Died10 February 1923 (aged 77)
Munich, Germany
NationalityGerman
FieldsPhysics
InstitutionsUniversity of Strassburg
Hohenheim
University of Giessen
University of Würzburg
University of Munich
Alma materETH Zurich
University of Zürich
Doctoral advisorAugust Kundt
Doctoral studentsHerman March
Abram Ioffe
Ernst Wagner
Known forX-rays
Notable awardsNobel Prize in Physics (1901)
Wilhelm Conrad Röntgen(27 March 1845 – 10 February 1923) was aGerman physicist, who, on 8 November 1895, produced and detected electromagnetic radiation in a wavelengthrange today known as x-raysor Röntgen rays, an achievement that earned him the first Nobel Prize in Physics in 1901.[1]:1
Following transliteration conventions for characters accented by an umlaut, "Röntgen" in English is spelled "Roentgen", and that is the usual rendering found in English-language scientific and medical references.

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[edit]Biography

Röntgen was born in Lennep (which is today a borough ofRemscheid) in Rhenish Prussia as the only child of a merchant and manufacturer of cloth. His mother was Charlotte Constanze Frowein of Amsterdam. In March 1848, the family moved to Apeldoorn and Wilhelm was raised in the Netherlands. He received his early education at the boarding school, Institute of Martinus Herman van Doorn, in Apeldoorn. From 1861 to 1863, he attended the ambachtsschool in Utrecht. He was expelled for refusing to reveal the identity of a classmate guilty of drawing an unflattering portrait of one of the school's teachers. Not only was he expelled, he subsequently found that he could not gain admittance into any other Dutch or German gymnasium.[2]
In 1865, he tried to attend the University of Utrecht without having the necessary credentials required for a regular student. Upon hearing that he could enter theFederal Polytechnic Institute in Zurich (today known as the ETH Zurich), he passed its examinations, and began studies there as a student of mechanical engineering. In 1869, he graduated with a Ph.D. from the University of Zurich; once there, he became a favorite student of Professor August Kundt, whom he followed to the University of Strassburg in 1873.[3]
Birthplace of Roentgen in Remscheid-Lennep

[edit]Career

In 1874 Röntgen became a lecturer at the University of Strassburg. In 1875 he became a professor at theAcademy of Agriculture atHohenheim, Württemberg. He returned to Strassburg as a professor of physics in 1876, and in 1879, he was appointed to the chair of physics at the University of Giessen. In 1888, he obtained the physics chair at theUniversity of Würzburg, and in 1900 at the University of Munich, by special request of the Bavarian government. Röntgen had family in Iowa in the United States and at one time planned to emigrate. Although he accepted an appointment at Columbia University in New York City and had actually purchased transatlantic tickets, the outbreak of World War I changed his plans and he remained in Munich for the rest of his career.

[edit]Discovery of x-rays

Hand mit Ringen: print of Wilhelm Röntgen's first "medical" x-ray, of his wife's hand, taken on 22 December 1895 and presented to Professor Ludwig Zehnder of the Physik Institut, University of Freiburg, on 1 January 1896[4][5]
An x-ray picture (radiograph) taken by Röntgen of Albert von Kölliker's hand at a public lecture on 23 January 1896[6]
During 1895 Röntgen was investigating the external effects from the various types of vacuum tubeequipment — apparatus fromHeinrich Hertz, Johann Hittorf,William Crookes, Nikola Tesla andPhilipp von Lenard — when an electrical discharge is passed through them.[7] In early November he was repeating an experiment with one of Lenard's tubes in which a thinaluminium window had been added to permit the cathode rays to exit the tube but a cardboard covering was added to protect the aluminium from damage by the strong electrostatic field that is necessary to produce the cathode rays. He knew the cardboard covering prevented light from escaping, yet Röntgen observed that the invisible cathode rays caused afluorescent effect on a small cardboard screen painted with barium platinocyanide when it was placed close to the aluminium window. It occurred to Röntgen that the Hittorf-Crookes tube, which had a much thicker glass wall than the Lenard tube, might also cause this fluorescent effect.
In the late afternoon of 8 November 1895, Röntgen determined to test his idea. He carefully constructed a black cardboard covering similar to the one he had used on the Lenard tube. He covered the Hittorf-Crookes tube with the cardboard and attached electrodes to a Ruhmkorff coil to generate anelectrostatic charge. Before setting up the barium platinocyanide screen to test his idea, Röntgen darkened the room to test the opacity of his cardboard cover. As he passed the Ruhmkorff coil charge through the tube, he determined that the cover was light-tight and turned to prepare the next step of the experiment. It was at this point that Röntgen noticed a faint shimmering from a bench a meter away from the tube. To be sure, he tried several more discharges and saw the same shimmering each time. Striking a match, he discovered the shimmering had come from the location of the barium platinocyanide screen he had been intending to use next.
Röntgen speculated that a new kind of ray might be responsible. 8 November was a Friday, so he took advantage of the weekend to repeat his experiments and make his first notes. In the following weeks he ate and slept in his laboratory as he investigated many properties of the new rays he temporarily termed X-rays, using the mathematical designation for something unknown. Although the new rays would eventually come to bear his name in many languages where they became known as Röntgen Rays, he always preferred the term X-rays. Nearly two weeks after his discovery, he took the very first picture using x-rays of his wife's hand, Anna Bertha. When she saw her skeleton she exclaimed "I have seen my death!"
The idea that Röntgen happened to notice the barium platinocyanide screen misrepresents his investigative powers; he had planned to use the screen in the next step of his experiment and would therefore have made the discovery a few moments later.[vague]
At one point while he was investigating the ability of various materials to stop the rays, Röntgen brought a small piece of lead into position while a discharge was occurring. Röntgen thus saw the first radiographic image, his own flickering ghostly skeleton on the barium platinocyanide screen. He later reported that it was at this point that he determined to continue his experiments in secrecy, because he feared for his professional reputation if his observations were in error.
Röntgen's original paper, "On A New Kind Of Rays" (Über eine neue Art von Strahlen), was published 50 days later on 28 December 1895. On 5 January 1896, an Austrian newspaper reported Röntgen's discovery of a new type ofradiation. Röntgen was awarded an honorary Doctor of Medicine degree from theUniversity of Würzburg after his discovery. He published a total of three papers on X-rays between 1895 and 1897. Today, Röntgen is considered the father ofdiagnostic radiology, the medical specialty which uses imaging to diagnose disease.

[edit]Personal life

Röntgen was married to Anna Bertha Ludwig (m. 1872, d. 1919) and had one child, Josephine Bertha Ludwig. Adopted at age 6, in 1887, she was the daughter of Anna's brother.[8] Röntgen died on 10 February 1923 from carcinomaof the intestine.[9] It is not believed his carcinoma was a result of his work with ionizing radiation because of the brief time he spent on those investigations, and because he was one of the few pioneers in the field who used protective lead shields routinely. In keeping with his will, all his personal and scientific correspondence were destroyed upon his death.[6]

[edit]Honours and awards

In 1901 Röntgen was awarded the very first Nobel Prize in Physics. The award was officially "in recognition of the extraordinary services he has rendered by the discovery of the remarkable rays subsequently named after him". Röntgen donated the monetary reward from his Nobel Prize to his university. Like Pierre Curie, Röntgen refused to take out patents related to his discovery, as he wanted mankind as a whole to benefit from practical applications of the same (personal statement). He did not even want the rays to be named after him.[citation needed]

[edit]Legacy

Today, in Remscheid-Lennep, 40 kilometers east of Düsseldorf, is the house in which Roentgen was born in 1845 and the Deutsches Röntgen-Museum.[10]
The modern Japanese word for X-ray is still 'rentogen', a Japanization of his name.

[edit]See also

[edit]References

  1. ^ Novelline, Robert. Squire's Fundamentals of Radiology. Harvard University Press. 5th edition. 1997. ISBN 0674833392.
  2. ^ Friedman, Meyer; Friedman, Gerald W. (16 November 1998). Medicine's 10 Greatest Discoveries. New Haven, CT: Yale University Press. pp. 115.ISBN 0300075987.
  3. ^ Trevert, Edward (1988). Something About X-Rays for Everybody. Madison, WI: Medical Physics Publishing Corporation. pp. 4. ISBN 0944838057.
  4. ^ Kevles, Bettyann Holtzmann (1996). Naked to the Bone Medical Imaging in the Twentieth Century. Camden, NJ: Rutgers University Press. pp. 19–22.ISBN 0813523583.
  5. ^ Sample, Sharron (27 March 2007). "X-rays". The electromagnetic spectrum. NASA. Retrieved 3 December 2007.
  6. ^ a b Landwehr, Gottfried (1997). Hasse, A. ed. Röntgen centennial: X-rays in Natural and Life Sciences. Singapore: World Scientific. pp. 7–8. ISBN 981-02-3085-0.
  7. ^ Stanton, Arthur (23 January 1896), "Wilhelm Conrad Röntgen On a New Kind of Rays: translation of a paper read before the Würzburg Physical and Medical Society, 1895", Nature 53: 274–6, doi:10.1038/053274b0
  8. ^ Glasser (1933: 63)
  9. ^ Glasser, Otto (1933). Wilhelm Conrad Röntgen and the Early History of the Roentgen Rays. London: John Bale, Sons and Danielsson, Ltd. p. 305.OCLC 220696336.
  10. ^ Deutsches Röntgen-Museum at www.roentgen-museum.de

[edit]External links

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