SHIPS EXPERIMENT:


Telescopes for Solar Hidden Photon Search Experiments

Ship pointing at Sun

Observing SHiPs

The SHIPS experiment targets the postu­lated solar Hidden Photons (HPs). Re-con­version of solar HPs into electro­magnetic photons occurs in a vacuum he­lio­scope, a modified astronomical Tele­scope for Solar Hidden Photon Search TSHIPS. TSHIPS are designed for con­ti­nuous observations of the Sun in the light of HPs. Imaging optics provides for contrast and spatial resolution.



SHIPS Experiment


SHIPS is an offspring of the ongoing ALPS projects at DESY. Unlike the laboratory experiments ALPS and ALPS II, SHIPS does not involve magnetic fields. The small TSHIPS are operated at the Hamburger Sternwarte.

The Solar Hidden Photon Search Ex­pe­ri­ment is carried out by the HS SHIPS team, with support from DESY and inspiration from Javier Redondo (MPP).

inside TSHIPS1

TSHIPS1 unwrapped
in the HS Library





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Concept

Solar Hidden Photons originate predo­mi­nant­ly in the photosphere. Weak coupling to the electromagnetic field causes oscillations between hν- and Hidden Photons. While in­ter­acting only very weakly with ordinary mat­ter, HPs have a finite pro­bability of con­verting into hν in a vacuum. Propagating along the trajec­to­ries of their HP pro­ge­nitors, the re­processed photons are de­tected by an optical tele­scope, which itself must be totally solar-blind and shiel­ded from parasitic light. [Photons generated by HP oscillations in the vacuum between the Sun and the Earth cannot be dis­tin­guished from the over­whelming solar flux].
The SHIPS helioscope is an astro­nomical telescope with an optical system in a va­cuum. It can observe the Sun at night, but needs to account for the different real and apparent positions at larger zenith angles.

inside TSHIPS1
Photons (real) in the first TSHIPS helioscope at 10-6 mbar



see TSHIPS in action




SHIPS tube

TSHIPS1 in the laboratory




TSHIPS 1

TSHIPS1 is built from a 3mm stainless steel tube 26.1 cm in diameter with an overall length of 260 cm. The detection system employs photomultiplier tubes and Fresnel lenses. TSHIPS1 weighs in at 75 kg and will first be attached to the outside of the OLT's mechanical structure, using the Stern­warte's 1.2 m telescope as a remote-con­trolled astronomical mount.
The expected signal is proportional to the collecting area and the vacuum path length (oscillation length). The helioscope is de­signed to point continuously and over long periods at the Sun. The dual pointing and optical system allows for simultaneous back­ground measurements.

 TSHIPS1
TSHIPS1+2 mounted onto the OLT



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woelb_1

The TSHIPS 2 vault structure


The 2 m vault structure has been assembled from 50 cm segments welded together. It serves as a testbench for the much longer and wider TSHIPS3. TSHIPS1 and TSHIPS2 can be coupled to form a long helioscope, or operate independently.

Detectors

Available funding currently restricts the choice of detectors to 2 photomultiplier tubes and a low-noise CCD camera. PMTs and CCDs are cooled to minimize dark current noise. Their performance and trade-offs are under study.


ccds

CCDs



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Optics

The initial imaging system comprises inexpensive lightweight f/1 Fresnel lenses.


Fresnel Lens

Solar light concentrator for HPs



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Under Development: TSHIPS 3




THIPS3 will use a ca. 8m long tube of 1 m diameter. An 8 m dummy has been con­structed to verify the design and operations plan for TSHIPS3 at the OLT.

TSHIPS3 will be put on a separate large alt-az mount for long-term operation. A proposal to transfer TSHIPS3 to the DESY premises is under discussion.

SHIP3

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woetas
WÖTAS* -Largest Reptile Species of the TSHIPS Family - in Action : Searching for Hidden Photons in Dark Matter

*WÖlbstrukturTeleskopfürAStroparticles; Art design by A-L.L.


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Funding

SHIPS is a minor project of the SFB676 (TSHIPS1)










© Hamburger Sternwarte, Universität Hamburg