Abstract
Up to now, 35 rock reliefs have been identified from the Sassanid period, one of them is located outside the political borders of Iran, at the site known as the Rag-e Bibi in Afghanistan. 34 other rock reliefs have been discovered inside Iran’s political borders in various regions such as: Rey city, Taq-e Bustan, Salmas, Barm-e Delak, Goyum, Tang-e chogan of Bishapour, Naqsh-e Rostam, Naqsh-e Rajab, Sarab-e Bahram, Tangab-e Firouzabad, Darabgerd, Tang-e Qandil and Sar Mashhad. Although all of these rock reliefs were studied by archaeologists and domestic and foreign researchers repeatedly, but most studies have focused on identifying the main character of the rock reliefs -the Sassanid king. And there is no serious and diligent attempt at identifying other characters on the scene. Of course, some scholars tried to clarify the true identity of some of the characters in the Sasanian rock reliefs. But most of them did not succeed. Because most of these identities are based on speculation. However, identifying individuals in the Sasanian rock reliefs should be based on historical evidence or face recognition or semiotic studies. For example, some researchers said that the character discussed in this article should be the servant of the king. Some also said that he should be the representative of the Karin family. In this research, which is based on the purpose of basic research and based on the nature and method of historical research, was attempted to clarify the true identity of one of the characters in the rock reliefs of Ardashir Babakan with the help of historical evidence, face recognition and semiotic studies. The results of the studies show that the person present in the rock reliefs of Ardashir Babakan should be Tansar. An influential clergyman who has been tried to spread Zoroastrianism and to regulate the texts of Avesta, and helped Ardashir Babakan to reach power and also helped him stabilize his power. 
Keywords: Sasanian Rock Reliefs, Ardashir Babakan, Tansar, Historicl Approach, Face Recognition, Semiotic.

Introduction
Personology of Sassanid reliefs raised debates among researchers, because of same thematic models of Sassanid kings and lack of inscriptions. Present paper discusses Ardashir’s relief of investiture and crowned by Ahuramazda. 
The research is based on the purpose of basic research and based on the nature and method of historical research, whereas collected data bibliographically, identification and thorough study of different written historical sources, and fieldwork, visiting Ardashir’s reliefs at Tanganb Firuzabad, Naqsh-i-Rajab and Naqsh-i-Rostam. Comparative study of historical sources and analytical approach at archaeological evidences and using historical approache are the methods to analyze and interpret data. 

Visual Evidence and Semiotics
Sassanid martial activities initiated years earlier that Ardashir to overcome Persia. Different factors caused clergymen raised to power and became influential through Sassanid rule (Hosseini 1392). Ardashir Babakan was a priest of Anahita temple at Istakhr, Fars (Christensen 1367: 134) enjoyed and joined dissatisfied clergymen to his government and endowed them high positions; it was his philosophy because his new ruling based on religious power and aristocracy that concluded to unification of religion and ruling (Hosseini 1392). As conclusion, one can say Ardashir needed clergymen confirm him to legitimize his ruling. Direct relation and superiority on people, doubled acceptance and support of clergymen. Following study of historic and written sources on presence of a cleric figure alongside Ardashir, firstly there is need to involve in similar visual parameters of the relief, which is identified earlier, for personological studies of the figure. In order to conclude, figure of Kartir is the best option, among options, because of the similarities to target figure, on the other hand, we know Kartir for the badge on his hat (Moosavi Haji 13996: 166); powerful face with shaved face, a badged hat, and his hair that came out of his hat on neck (fig. 5). His official custom is a long robe to his knee and a belt with a sheath (fig. 6). All explanation about his appearance is comparable to our target figure, so one could suggest that the appearance characteristic of Sassanid clergymen relied on the same pattern and tradition. However, every clergyman has common characteristic in every given religion. 

Conclusion 
Accordingly, one could conclude:
- It is not logical that a neutral person, a servant, would be carved on a public media such as a royal relief, let alone in a scene of investiture ceremony and crowning of Ardashir as the representative of Ahuramazda on earth. 
- No servant allowed to hold sword.
- Accordingly, Ardashir always needed general legitimation and acceptance that could be facilitated by a chosen religious figure at people. 
- Considering Sassanid and further written and historical sources, presence of Tansar as great supporter and evangelist is undeniable. His appearance in the relief matches to the discussion of present paper. 
- Visual composition and evidences of the figure, garment, shaven face, hat, and hairs are completely similar to great clergyman Kartir of later Sassanid period, so one could probably suggest it as general homogeny of the clothing of clerics during Sassanid period. 
- Badge of the figure, is completely similar to Kartir’s badge, on the other hand, adaptable to fire altar of reverse of coins of Persid period. Persids ruled Fars province during Seleucid and Parthian eras, who were eager to religious issues, so some scholars name them “fire servants”. 
- The target figure is present at Sassanid sources and religious events of Ardashir reign, but according written sources, Kartir replaced him after this period with no further trace on reliefs.